LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
LMR12015/LMR12020 SIMPLE SWITCHER
®
20Vin, 1.5A/2A Step-Down Voltage Regulator
in WSON-10
Check for Samples: LMR12015,LMR12020
1FEATURES DESCRIPTION
The LMR12015/20 regulator is a monolithic, high
23 Space Saving 3 x 3 x 0.8 mm WSON-10 frequency, PWM step-down DC-DC converter in a 10-
Package pin WSON package. It contains all the active
Input Voltage Range of 3V to 20V functions to provide local DC-DC conversion with fast
Output Voltage Range of 1V to 18V transient response and accurate regulation in the
smallest possible PCB area.
LMR12015 and LMR12020 Deliver 1.5A and 2A
Maximum Output Current Respectively With a minimum of external components the
LMR12015/20 is easy to use. The ability to drive
2 MHz Switching Frequency 1.5/2A loads respectively, with an internal 150 m
Frequency Synchronization from 1.00 MHz to NMOS switch results in the best power density
2.35 MHz available. The control circuitry allows for on-times as
70 nA Shutdown Current low as 65 ns, thus supporting exceptionally high
frequency conversion. Switching frequency is
1% Voltage Reference Accuracy internally set to 2 MHz and synchronizable from 1 to
Peak Current Mode PWM Operation 2.35 MHz, which allows the use of extremely small
Thermal Shutdown surface mount inductors and chip capacitors. Even
though the operating frequency is very high,
Internally Compensated efficiencies up to 90% are easy to achieve. External
Internal Soft-Start shutdown is included featuring an ultra-low shutdown
WEBENCH®Enabled current of 70 nA. The LMR12015/20 utilizes peak
current mode control and internal compensation to
PERFORMANCE BENEFITS provide high-performance regulation over a wide
range of operating conditions. Additional features
Tight Accuracy for Powering Digital ICs include internal soft-start circuitry to reduce inrush
Extremely Easy to Use current, pulse-by-pulse current limit, thermal
Tiny Overall Solution Reduces System Cost shutdown, and output over-voltage protection.
APPLICATIONS
Point-of-Load Conversions from 3.3V, 5V and
12V Rails
Space Constrained Applications
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2SIMPLE SWITCHER, WEBENCH are registered trademarks of Texas Instruments.
3All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2012–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
2
3
47
9
8
PVIN
SW
EN
DAP AVIN
GND
BOOST
6
10
1
5
SYNC FB
SW PVIN
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND/DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
CLK
ON
OFF
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
40
46
52
58
64
70
76
82
88
94
100
EFFICIENCY (%)
IOUT(A)
Vin = 7V
Vin = 8V
Vin = 10V
Vin = 12V
Vin = 14V
Vin = 16V
Vin = 18V
Vin = 20V
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1
45
50
55
60
65
70
75
80
85
90
95
EFFICIENCY (%)
IOUT(A)
Vin = 5V
Vin = 7V
Vin = 9V
Vin = 12V
Vin = 14V
Vin = 16V
Vin = 18V
Vin = 20
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
System Performance
Efficiency vs Load Current Efficiency vs Load Current
LMR12015/20 VOUT = 5V, fsw = 2 MHz LMR12015/20 VOUT = 3.3V, fsw = 2 MHz
Typical Application Circuit
Connection Diagram
10 - Lead WSON (Top View)
See Package Number DSC
2Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
PIN DESCRIPTIONS
Pin Name Function
1,2 SW Output switch. Connects to the inductor, catch diode, and bootstrap capacitor.
3 BOOST Boost voltage that drives the internal NMOS control switch. A bootstrap capacitor is connected between the
BOOST and SW pins.
4 EN Enable control input. Logic high enables operation. Do not allow this pin to float or be greater than VIN + 0.3V.
5 SYNC Frequency synchronization input. Drive this pin with an external clock or pulse train. Ground it to use the
internal clock.
6 FB Feedback pin. Connect FB to the external resistor divider to set output voltage.
7 GND Signal and Power Ground pin. Place the bottom resistor of the feedback network as close as possible to this
pin for accurate regulation.
8 AVIN Supply voltage for the control circuitry.
9,10 PVIN Supply voltage for output power stage. Connect a bypass capacitor to this pin.
DAP GND Signal / Power Ground and thermal connection. Tie this directly to GND (pin 7). See APPLICATION
INFORMATION regarding optimum thermal layout.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
Absolute Maximum Ratings(1)(2)
AVIN, PVIN -0.5V to 24V
SW Voltage -0.5V to 24V
Boost Voltage -0.5V to 28V
Boost to SW Voltage -0.5V to 6.0V
FB Voltage -0.5V to 3.0V
SYNC Voltage -0.5V to 6.0V
EN Voltage -0.5V to (VIN + 0.3V)
Storage Temperature Range -65°C to +150°C
Junction Temperature 150°C
ESD Susceptibility(3) 2kV
Soldering Information
Infrared Reflow (5sec) 260°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including inoperability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the recommended Operating Ratings is not implied. The recommended Operating Ratings
indicate conditions at which the device is functional and should not be operated beyond such conditions.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) Human body model, 1.5 kin series with 100 pF.
Operating Ratings(1)
AVIN, PVIN 3V to 20V
SW Voltage -0.5V to 20V
Boost Voltage -0.5V to 24V
Boost to SW Voltage 3.0V to 5.5V
Junction Temperature Range -40°C to +125°C
Thermal Resistance (θJA) WSON (DSC)(2) 33°C/W
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including inoperability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the recommended Operating Ratings is not implied. The recommended Operating Ratings
indicate conditions at which the device is functional and should not be operated beyond such conditions.
(2) All numbers apply for packages soldered directly onto a 3” x 3” PC board with 2oz. copper on 4 layers in still air.
4Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
Electrical Characteristics
Specifications with standard typeface are for TJ= 25°C, and those in boldface type apply over the full Operating
Temperature Range (TJ= -40°C to 125°C). VIN = 12V, and VBOOST - VSW = 4.3V unless otherwise specified. Datasheet
min/max specification limits are ensured by design, test, or statistical analysis.
Symbol Parameter Conditions Min Typ Max Units
SYSTEM PARAMETERS
TJ= 0°C to 85°C 0.990 1.0 1.010
VFB Feedback Voltage V
TJ= -40°C to 125°C 0.984 1.0 1.014
ΔVFB/ΔVIN Feedback Voltage Line Regulation VIN = 3V to 20V 0.003 % / V
IFB Feedback Input Bias Current 20 100 nA
Over Voltage Protection, VFB at
OVP 1.13 V
which PWM Halts.
Undervoltage Lockout VIN Rising until VSW is Switching 2.60 2.75 2.90
UVLO V
UVLO Hysteresis VIN Falling from UVLO 0.30 0.47 0.6
SS Soft Start Time 0.5 1 1.5 ms
Quiescent Current, IQ= IQ_AVIN +VFB = 1.1 (not switching) 2.4 mA
IQ_PVIN
IQQuiescent Current, IQ= IQ_AVIN +VEN = 0V (shutdown) 70 nA
IQ_PVIN fSW= 2 MHz 8.2 10
IBOOST Boost Pin Current mA
fSW= 1 MHz 4.4 6
OSCILLATOR
fSW Switching Frequency SYNC = GND 1.75 22.3 MHz
FB Pin Voltage where SYNC input is
VFB_FOLD 0.53 V
overridden.
fFOLD_MIN Frequency Foldback Minimum VFB = 0V 220 250 kHz
LOGIC INPUTS (EN, SYNC)
fSYNC SYNC Frequency Range 1 2.35 MHz
VIL EN, SYNC Logic low threshold Logic Falling Edge 0.4 V
VIH EN, SYNC Logic high threshold Logic Rising Edge 1.8
SYNC, Time Required above VIH to
tSYNC_HIGH 100 ns
Ensure a Logical High.
SYNC, Time Required below VIL to
tSYNC_LOW 100 ns
Ensure a Logical Low.
ISYNC SYNC Pin Current VSYNC < 5V 20 nA
VEN = 3V 6 15
IEN Enable Pin Current µA
VIN = VEN = 20V 50 100
INTERNAL MOSFET
RDS(ON) Switch ON Resistance 150 320 m
ICL Switch Current Limit LMR12020 2.5 4.0 A
LMR12015 2.0 3.7
DMAX Maximum Duty Cycle SYNC = GND 85 93 %
tMIN Minimum on time 65 ns
ISW Switch Leakage Current 40 nA
BOOST LDO
VLDO Boost LDO Output Voltage 3.9 V
THERMAL
TSHDN Thermal Shutdown Temperature(1) Junction temperature rising 165 °C
Thermal Shutdown Hysteresis Junction temperature hysteresis 15 °C
(1) Thermal shutdown will occur if the junction temperature exceeds 165°C. The maximum power dissipation is a function of TJ(MAX) ,θJA
and TA. The maximum allowable power dissipation at any ambient temperature is PD= (TJ(MAX) TA)/θJA .
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: LMR12015 LMR12020
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1
45
50
55
60
65
70
75
80
85
90
95
EFFICIENCY (%)
IOUT(A)
Vin = 5V
Vin = 7V
Vin = 9V
Vin = 12V
Vin = 14V
Vin = 16V
Vin = 18V
Vin = 20
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
40
46
52
58
64
70
76
82
88
94
100
EFFICIENCY (%)
IOUT(A)
Vin = 7V
Vin = 8V
Vin = 10V
Vin = 12V
Vin = 14V
Vin = 16V
Vin = 18V
Vin = 20V
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS
All curves taken at VIN = 12V, VBOOST - VSW = 4.3V and TA= 25°C, unless specified otherwise.
Efficiency vs Load Current Load Transient
VOUT = 5V, fSW = 2 MHz VOUT = 5V, IOUT = 100 mA - 2A @ slewrate = 2A / µs
Refer to Figure 37 Refer to Figure 37
Figure 1. Figure 2.
Efficiency vs Load Current Load Transient
VOUT = 3.3V, fSW = 2 MHz VOUT = 3.3V, IOUT = 100 mA - 2A @ slewrate = 2A / µs
Refer to Figure 39 Refer to Figure 39
Figure 3. Figure 4.
Efficiency vs Load Current Load Transient
VOUT = 1.8V, fSW = 2 MHz VOUT = 1.8V, IOUT = 100 mA - 2A @ slewrate = 2A / µs
Refer to Figure 40 Refer to Figure 40
Figure 5. Figure 6.
6Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
All curves taken at VIN = 12V, VBOOST - VSW = 4.3V and TA= 25°C, unless specified otherwise.
Line Transient Line Transient
VIN = 10 to 15V, VOUT = 3.3V, no CFF VIN = 10 to 15V, VOUT = 3.3V
Refer to Figure 39 Refer to Figure 38
Figure 7. Figure 8.
Short Circuit Short Circuit Release
Figure 9. Figure 10.
Soft Start Soft Start with EN Tied to VIN
Figure 11. Figure 12.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 7
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
All curves taken at VIN = 12V, VBOOST - VSW = 4.3V and TA= 25°C, unless specified otherwise.
VIN = 12V, VOUT = 5 V, L = 2.2 µH, COUT = 44 µF Iout =1A VIN = 12V, VOUT = 3.3V, L = 1.5 µH COUT = 44 µF Iout =1A
Figure 13. Figure 14.
VIN = 5V, VOUT = 1.8V, L = 1.0 µH COUT = 44 µF Iout =1A VIN = 5V, VOUT = 1.2V, L = 0.56 µH COUT = 68 µF Iout =1A
Figure 15. Figure 16.
Sync Functionality Loss of Synchronization
Figure 17. Figure 18.
8Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
All curves taken at VIN = 12V, VBOOST - VSW = 4.3V and TA= 25°C, unless specified otherwise.
Oscillator Frequency vs Temperature Oscillator Frequency vs VFB
VSYNC = GND VSYNC = GND
Figure 19. Figure 20.
VFB vs Temperature VFB vs VIN
Figure 21. Figure 22.
Current Limit vs Temperature
VIN = 12V RDSON vs Temperature
Figure 23. Figure 24.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 9
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
All curves taken at VIN = 12V, VBOOST - VSW = 4.3V and TA= 25°C, unless specified otherwise.
IQ(Shutdown) vs Temperature
IQ= IAVIN + IPVIN IEN vs VEN
Figure 25. Figure 26.
10 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
RSENSE
PWM Logic
Driver
+
-
Switch
0.15:
FB
Error Amplifier
SYNC
Freq. Foldback Amplifier
-
+
VREF
1.0V
+
-
1.13V
-
+
OVP Comparator
+
-
-
+
0.53V
+
-
Thermal
Shutdown
Current
Limit
LDO
EN
PVIN
AVIN
BOOST
SW
L
C3
C2
VOUT
GND
Under
Voltage
Lockout
Corrective
Ramp
++
ISENSE
Reset
Pulse
PWM
Comparator
Error
Signal
Oscillator Internal
Compensation
Soft Start
+
-
+
Current Sense
Amplifier
D2
D1
iL
R1
R2
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
Block Diagram
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Links: LMR12015 LMR12020
0
0
VIN
-VD1
tON
t
t
Inductor Current
D = tON/TSW
VSW
tOFF
TSW
iL
SW Voltage
'iL
IOUT
ILPK
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
APPLICATION INFORMATION
THEORY OF OPERATION
The LMR12015/20 is a constant-frequency, peak current-mode PWM buck regulator IC that delivers a 1.5 or 2A
load current. The regulator has a preset switching frequency of 2 MHz. This high frequency allows the
LMR12015/20 to operate with small surface mount capacitors and inductors, resulting in a DC-DC converter that
requires a minimum amount of board space. The LMR12015/20 is internally compensated, which reduces design
time, and requires few external components.
The following operating description of the LMR12015/20 will refer to the Block Diagram and to the waveforms in
Figure 27. The LMR12015/20 supplies a regulated output voltage by switching the internal NMOS switch at a
constant frequency and varying the duty cycle. A switching cycle begins at the falling edge of the reset pulse
generated by the internal oscillator. When this pulse goes low, the output control logic turns on the internal
NMOS switch. During this on-time, the SW pin voltage (VSW) swings up to approximately VIN, and the inductor
current (iL) increases with a linear slope. The current-sense amplifier measures iL, which generates an output
proportional to the switch current typically called the sense signal. The sense signal is summed with the
regulator’s corrective ramp and compared to the error amplifier’s output, which is proportional to the difference
between the feedback voltage (VFB) and VREF. When the output of the PWM comparator goes high, the switch
turns off until the next switching cycle begins. During the switch off-time (tOFF), inductor current discharges
through the catch diode D1, which forces the SW pin (VSW) to swing below ground by the forward voltage (VD1)
of the catch diode. The regulator loop adjusts the duty cycle (D) to maintain a constant output voltage.
Figure 27. LMR12015/20 Waveforms of SW Pin Voltage and Inductor Current
12 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND/DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
CLK
ON
OFF
5V
D2
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
BOOST FUNCTION
Capacitor C2in Block Diagram, commonly referred to as CBOOST, is used to store a voltage VBOOST. When the
LMR12015/20 starts up, an internal LDO charges CBOOST ,via an internal diode, to a voltage sufficient to turn the
internal NMOS switch on. The gate drive voltage supplied to the internal NMOS switch is VBOOST - VSW.
During a normal switching cycle, when the internal NMOS control switch is off (tOFF) (refer to Figure 27), VBOOST
equals VLDO minus the forward voltage of the internal diode (VD2). At the same time the inductor current (iL)
forward biases the catch diode D1 forcing the SW pin to swing below ground by the forward voltage drop of the
catch diode (VD1). Therefore, the voltage stored across CBOOST is
VBOOST - VSW = VLDO - VD2 + VD1 (1)
Thus,VBOOST = VSW + VLDO - VD2 + VD1 (2)
When the NMOS switch turns on (tON), the switch pin rises to
VSW = VIN (RDSON x IL), (3)
reverse biasing D1, and forcing VBOOST to rise. The voltage at VBOOST is then
VBOOST = VIN (RDSON x IL) + VLDO VD2 + VD1 (4)
which is approximately
VIN + VLDO- 0.4V (5)
VBOOST has pulled itself up by its "bootstraps", or boosted to a higher voltage.
LOW INPUT VOLTAGE CONSIDERATIONS
When the input voltage is below 5V and the duty cycle is greater than 75 percent, the gate drive voltage
developed across CBOOST might not be sufficient for proper operation of the NMOS switch. In this case, CBOOST
should be charged via an external Schottky diode attached to a 5V voltage rail, see Figure 28. This ensures that
the gate drive voltage is high enough for proper operation of the NMOS switch in the triode region. Maintain
VBOOST - VSW less than the 6V absolute maximum rating.
Figure 28. External Diode Charges CBOOST
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LMR12015 LMR12020
R3 =VIN - 1
1.8 x R4
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
HIGH OUTPUT VOLTAGE CONSIDERATIONS
When the output voltage is greater than 3.3V, a minimum load current is needed to charge CBOOST, see
Figure 29. The minimum load current forward biases the catch diode D1 forcing the SW pin to swing below
ground. This allows CBOOST to charge, ensuring that the gate drive voltage is high enough for proper operation.
The minimum load current depends on many factors including the inductor value.
Figure 29. Minimum Load Current for L = 1.5 µH
ENABLE PIN / SHUTDOWN MODE
Connect the EN pin to a voltage source greater than 1.8V to enable operation of the LMR12015/20. Apply a
voltage less than 0.4V to put the part into shutdown mode. In shutdown mode the quiescent current drops to
typically 70 nA. Switch leakage adds another 40 nA from the input supply. For proper operation, the
LMR12015/20 EN pin should never be left floating, and the voltage should never exceed VIN + 0.3V.
The simplest way to enable the operation of the LMR12015/20 is to connect the EN pin to AVIN which allows self
start-up of the LMR12015/20 when the input voltage is applied.
When the rise time of VIN is longer than the soft-start time of the LMR12015/20 this method may result in an
overshoot in output voltage. In such applications, the EN pin voltage can be controlled by a separate logic signal,
or tied to a resistor divider, which reaches 1.8V after VIN is fully established (see Figure 30). This will minimize
the potential for output voltage overshoot during a slow VIN ramp condition. Use the lowest value of VIN , seen in
your application when calculating the resistor network, to ensure that the 1.8V minimum EN threshold is reached.
Figure 30. Resistor Divider on EN
(6)
14 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
FREQUENCY SYNCHRONIZATION
The LMR12015/20 switching frequency can be synchronized to an external clock, between 1.00 and 2.35 MHz,
applied at the SYNC pin. At the first rising edge applied to the SYNC pin, the internal oscillator is overridden and
subsequent positive edges will initiate switching cycles. If the external SYNC signal is lost during operation, the
LMR12015/20 will revert to its internal 2 MHz oscillator within 1.5 µs. To disable Frequency Synchronization and
utilize the internal 2 MHz oscillator, connect the SYNC pin to GND.
The SYNC pin gives the designer the flexibility to optimize their design. A lower switching frequency can be
chosen for higher efficiency. A higher switching frequency can be chosen to keep EMI out of sensitive ranges
such as the AM radio band. Synchronization can also be used to eliminate beat frequencies generated by the
interaction of multiple switching power converters. Synchronizing multiple switching power converters will result
in cleaner power rails.
The selected switching frequency (fSYNC) and the minimum on-time (tMIN) limit the minimum duty cycle (DMIN) of
the device.
DMIN= tMIN x fSYNC (7)
Operation below DMIN is not reccomended. The LMR12015/20 will skip pulses to keep the output voltage in
regulation, and the current limit is not ensured. The switching is in phase but no longer at the same switching
frequency as the SYNC signal.
CURRENT LIMIT
The LMR12015/20 use cycle-by-cycle current limiting to protect the output switch. During each switching cycle, a
current limit comparator detects if the output switch current exceeds 2.0A min (LMR12015) or 2.5A min
(LMR12020) , and turns off the switch until the next switching cycle begins.
FREQUENCY FOLDBACK
The LMR12015/20 employs frequency foldback to protect the device from current run-away during output short-
circuit. Once the FB pin voltage falls below regulation, the switch frequency will smoothly reduce with the falling
FB voltage until the switch frequency reaches 220 kHz (typ). If the device is synchronized to an external clock,
synchronization is disabled until the FB pin voltage exceeds 0.53V
SOFT-START
The LMR12015/20 has a fixed internal soft-start of 1 ms (typ). During soft-start, the error amplifier’s reference
voltage ramps from 0.0 V to its nominal value of 1.0 V in approximately 1 ms. This forces the regulator output to
ramp in a controlled fashion, which helps reduce inrush current. Upon soft-start the part will initially be in
frequency foldback and the frequency will rise as FB rises. The regulator will gradually rise to 2 MHz. The
LMR12015/20 will allow synchronization to an external clock at FB > 0.53V.
OUTPUT OVERVOLTAGE PROTECTION
The overvoltage comparator turns off the internal power NFET when the FB pin voltage exceeds the internal
reference voltage by 13% (VFB > 1.13 * VREF). With the power NFET turned off the output voltage will decrease
toward the regulation level.
UNDERVOLTAGE LOCKOUT
Undervoltage lockout (UVLO) prevents the LMR12015/20 from operating until the input voltage exceeds
2.75V(typ).
The UVLO threshold has approximately 470 mV of hysteresis, so the part will operate until VIN drops below
2.28V(typ). Hysteresis prevents the part from turning off during power up if VIN has finite impedance.
THERMAL SHUTDOWN
Thermal shutdown limits total power dissipation by turning off the internal NMOS switch when the IC junction
temperature exceeds 165°C (typ). After thermal shutdown occurs, hysteresis prevents the internal NMOS switch
from turning on until the junction temperature drops to approximately 150°C.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: LMR12015 LMR12020
r = 'iL
lOUT
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
Design Guide
INDUCTOR SELECTION
Inductor selection is critical to the performance of the LMR12015/20. The selection of the inductor affects
stability, transient response and efficiency. A key factor in inductor selection is determining the ripple current (ΔiL)
(see Figure 27).
The ripple current (ΔiL) is important in many ways.
First, by allowing more ripple current, lower inductance values can be used with a corresponding decrease in
physical dimensions and improved transient response. On the other hand, allowing less ripple current will
increase the maximum achievable load current and reduce the output voltage ripple (see Output Capacitor
section for more details on calculating output voltage ripple). Increasing the maximum load current is achieved by
ensuring that the peak inductor current (ILPK) never exceeds the minimum current limit of 2.0A min (LMR12015)
or 2.5A min (LMR12020) .
ILPK = IOUT +ΔiL/ 2 (8)
Secondly, the slope of the ripple current affects the current control loop. The LMR12015/20 has a fixed slope
corrective ramp. When the slope of the current ripple becomes significantly less than the converter’s corrective
ramp (see Block Diagram), the inductor pole will move from high frequencies to lower frequencies. This negates
one advantage that peak current-mode control has over voltage-mode control, which is, a single low frequency
pole in the power stage of the converter. This can reduce the phase margin, crossover frequency and potentially
cause instability in the converter. Contrarily, when the slope of the ripple current becomes significantly greater
than the converter’s corrective ramp, resonant peaking can occur in the control loop. This can also cause
instability (Sub-Harmonic Oscillation) in the converter. For the power supply designer this means that for lower
switching frequencies the current ripple must be increased to keep the inductor pole well above crossover. It also
means that for higher switching frequencies the current ripple must be decreased to avoid resonant peaking.
With all these factors, how is the desired ripple current selected? The ripple ratio (r) is defined as the ratio of
inductor ripple current (ΔiL) to output current (IOUT), evaluated at maximum load:
(9)
A good compromise between physical size, transient response and efficiency is achieved when we set the ripple
ratio between 0.2 and 0.4. The recommended ripple ratio vs. duty cycle shown below (see Figure 31) is based
upon this compromise and control loop optimizations. Note that this is just a guideline. Please see Application
note AN-1197 SNVA038 for further considerations.
Figure 31. Recommended Ripple Ratio Vs. Duty Cycle
16 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
L = VOUT + VD1
IOUT x r x fSW x (1-DMIN)
D = VOUT + VD1
VIN + VD1 - VDS
D = VOUT
VIN
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
The Duty Cycle (D) can be approximated quickly using the ratio of output voltage (VOUT) to input voltage (VIN):
(10)
The application's lowest input voltage should be used to calculate the ripple ratio. The catch diode forward
voltage drop (VD1) and the voltage drop across the internal NFET (VDS) must be included to calculate a more
accurate duty cycle. Calculate D by using the following formula:
(11)
VDS can be approximated by:
VDS = IOUT x RDS(ON) (12)
The diode forward drop (VD1) can range from 0.3V to 0.5V depending on the quality of the diode. The lower VD1
is, the higher the operating efficiency of the converter.
Now that the ripple current or ripple ratio is determined, the required inductance is calculated by:
(13)
where DMIN is the duty cycle calculated with the maximum input voltage, fsw is the switching frequency, and IOUT
is the maximum output current of 2A. Using IOUT = 2A will minimize the inductor's physical size.
INDUCTOR CALCULATION EXAMPLE
Operating conditions for the LMR12015/20 are:
VIN = 7 - 16V (14)
fSW = 2 MHz (15)
VOUT = 3.3V (16)
VD1 = 0.5V (17)
IOUT = 2A (18)
First the maximum duty cycle is calculated.
DMAX= (VOUT + VD1) / (VIN + VD1 - VDS) = (3.3V + 0.5V) / (7V + 0.5V - 0.30V) = 0.528 (19)
Using Figure 31 gives us a recommended ripple ratio = 0.4.
Now the minimum duty cycle is calculated.
DMIN= (VOUT + VD1) / (VIN + VD1 - VDS) = (3.3V + 0.5V) / (16V + 0.5V - 0.30V) = 0.235 (20)
The inductance can now be calculated.
L= (1 - DMIN) x (VOUT + VD1) / (IOUT x r x fsw) = (1 - 0.235) x (3.3V + .5V) / (2A x 0.4 x 2 MHz) = 1.817 µH (21)
This is close to the standard inductance value of 1.8 µH. This leads to a 1% deviation from the recommended
ripple ratio, which is now 0.4038.
Finally, we check that the peak current does not reach the minimum current limit of 2.5A.
ILPK = IOUT x (1 + r / 2) = 2A x (1 + .4038 / 2 ) = 2.404A (22)
The peak current is less than 2.5A, so the DC load specification can be met with this ripple ratio. To design for
the LMR12015 simply replace IOUT = 1.5A in the equations for ILPK and see that ILPK does not exceed the
LMR12015's current limit of 2.0A (min).
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Links: LMR12015 LMR12020
IRMS-IN = IOUT x D x r2
12
1 - D +
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
INDUCTOR MATERIAL SELECTION
When selecting an inductor, make sure that it is capable of supporting the peak output current without saturating.
Inductor saturation will result in a sudden reduction in inductance and prevent the regulator from operating
correctly. To prevent the inductor from saturating over the entire -40 °C to 125 °C range, pick an inductor with a
saturation current higher than the upper limit of ICL listed in the Electrical Characteristics table.
Ferrite core inductors are recommended to reduce AC loss and fringing magnetic flux. The drawback of ferrite
core inductors is their quick saturation characteristic. The current limit circuit has a propagation delay and so is
oftentimes not fast enough to stop a saturated inductor from going above the current limit. This has the potential
to damage the internal switch. To prevent a ferrite core inductor from getting into saturation, the inductor
saturation current rating should be higher than the switch current limit ICL. The LMR12015/20 is quite robust in
handling short pulses of current that are a few amps above the current limit. Saturation protection is provided by
a second current limit which is 30% higher than the cycle by cycle current limit. When the saturation protection is
triggered the part will turn off the output switch and attempt to soft-start. (When a compromise has to be made,
pick an inductor with a saturation current just above the lower limit of the ICL.) Be sure to validate the short-circuit
protection over the intended temperature range.
An inductor's saturation current is usually lower when hot. So consult the inductor vendor if the saturation current
rating is only specified at room temperature.
Soft saturation inductors such as the iron powder types can also be used. Such inductors do not saturate
suddenly and therefore are safer when there is a severe overload or even shorted output. Their physical sizes
are usually smaller than the Ferrite core inductors. The downside is their fringing flux and higher power
dissipation due to relatively high AC loss, especially at high frequencies.
INPUT CAPACITOR
An input capacitor is necessary to ensure that VIN does not drop excessively during switching transients. The
primary specifications of the input capacitor are capacitance, voltage, RMS current rating, and Equivalent Series
Inductance (ESL). The recommended input capacitance is 10 µF, although 4.7 µF works well for input voltages
below 6V. The input voltage rating is specifically stated by the capacitor manufacturer. Make sure to check any
recommended deratings and also verify if there is any significant change in capacitance at the operating input
voltage and the operating temperature. The input capacitor maximum RMS input current rating (IRMS-IN) must be
greater than:
where
r is the ripple ratio defined earlier
IOUT is the output current, and
D is the duty cycle (23)
It can be shown from the above equation that maximum RMS capacitor current occurs when D = 0.5. Always
calculate the RMS at the point where the duty cycle, D, is closest to 0.5. The ESL of an input capacitor is usually
determined by the effective cross sectional area of the current path. A large leaded capacitor will have high ESL
and a 0805 ceramic chip capacitor will have very low ESL. At the operating frequencies of the LMR12015/20,
certain capacitors may have an ESL so large that the resulting impedance (2πfL) will be higher than that required
to provide stable operation. As a result, surface mount capacitors are strongly recommended. Sanyo POSCAP,
Tantalum or Niobium, Panasonic SP or Cornell Dubilier Low ESR are all good choices for input capacitors and
have acceptable ESL. Multilayer ceramic capacitors (MLCC) have very low ESL. For MLCCs it is recommended
to use X7R or X5R dielectrics. Consult the capacitor manufacturer's datasheet to see how rated capacitance
varies over operating conditions.
18 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
R1 =VOUT - 1
VREF x R2
IRMS-OUT = IOUT x r
12
'VOUT = 'iL x (RESR + 1
8 x fSW x COUT)
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
OUTPUT CAPACITOR
The output capacitor is selected based upon the desired output ripple and transient response. The
LMR12015/20's loop compensation is designed for ceramic capacitors. A minimum of 22 µF is required at 2 MHz
(33 uF at 1 MHz) while 47 - 100 µF is recommended for improved transient response and higher phase margin.
The output voltage ripple of the converter is:
(24)
When using MLCCs, the ESR is typically so low that the capacitive ripple may dominate. When this occurs, the
output ripple will be approximately sinusoidal and 90° phase shifted from the switching action. Another benefit of
ceramic capacitors is their ability to bypass high frequency noise. A certain amount of switching edge noise will
couple through parasitic capacitances in the inductor to the output. A ceramic capacitor will bypass this noise
while a tantalum will not.
The transient response is determined by the speed of the control loop and the ability of the output capacitor to
provide the initial current of a load transient. Capacitance can be increased significantly with little detriment to the
regulator stability. However, increasing the capacitance provides dimininshing improvement over 100 uF in most
applications, because the bandwidth of the control loop decreases as output capacitance increases. If improved
transient performance is required, add a feed forward capacitor. This becomes especially important for higher
output voltages where the bandwidth of the LMR12015/20 is lower. See Feed Forward Capacitor and Frequency
Synchronization sections.
Check the RMS current rating of the capacitor. The RMS current rating of the capacitor chosen must also meet
the following condition:
where
IOUT is the output current, and
r is the ripple ratio. (25)
CATCH DIODE
The catch diode (D1) conducts during the switch off-time. A Schottky diode is recommended for its fast switching
times and low forward voltage drop. The catch diode should be chosen so that its current rating is greater than:
ID1 = IOUT x (1-D) (26)
The reverse breakdown rating of the diode must be at least the maximum input voltage plus appropriate margin.
To improve efficiency choose a Schottky diode with a low forward voltage drop.
BOOST DIODE (OPTIONAL)
For circuits with input voltages VIN < 5V and duty cycles (D) >0.75V. a small-signal Schottky diode is
recommended. A good choice is the BAT54 small signal diode. The cathode of the diode is connected to the
BOOST pin and the anode to a 5V voltage rail.
BOOST CAPACITOR
A ceramic 0.1 µF capacitor with a voltage rating of at least 6.3V is sufficient. The X7R and X5R MLCCs provide
the best performance.
OUTPUT VOLTAGE
The output voltage is set using the following equation where R2 is connected between the FB pin and GND, and
R1 is connected between VOUT and the FB pin. A good starting value for R2 is 1 k.
(27)
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: LMR12015 LMR12020
CFF <= VOUT x COUT
IOUT x R1
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
FEED FORWARD CAPACITOR (OPTIONAL)
A feed forward capacitor CFF can improve the transient response of the converter. Place CFF in parallel with R1.
The value of CFF should place a zero in the loop response at, or above, the pole of the output capacitor and
RLOAD. The CFF capacitor will increase the crossover frequency of the design, thus a larger minimum output
capacitance is required for designs using CFF. CFF should only be used with an output capacitance greater than
or equal to 44 uF. Example waveforms of load transient with and without the CFF caps are as shown below.
(28)
Figure 32. LMR12015/20 Load Transient with CFF cap
VOUT = 3.3V
Figure 33. LMR12015/20 Load Transient without CFF cap
VOUT = 3.3V
20 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
D = VOUT + VD1 + VDCR
VIN + VD1 - VDS
D = VOUT + VD1
VIN + VD1 - VDS
K = POUT
POUT + PLOSS
K = POUT
PIN
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
Calculating Efficiency, and Junction Temperature
The complete LMR12015/20 DC-DC converter efficiency can be calculated in the following manner.
(29)
Or
(30)
Calculations for determining the most significant power losses are shown below. Other losses totaling less than
2% are not discussed.
Power loss (PLOSS) is the sum of two basic types of losses in the converter, switching and conduction.
Conduction losses usually dominate at higher output loads, where as switching losses remain relatively fixed and
dominate at lower output loads. The first step in determining the losses is to calculate the duty cycle (D).
(31)
VDS is the voltage drop across the internal NFET when it is on, and is equal to:
VDS = IOUT x RDSON (32)
VDis the forward voltage drop across the Schottky diode. It can be obtained from the Electrical Characteristics
section of the schottky diode datasheet. If the voltage drop across the inductor (VDCR) is accounted for, the
equation becomes:
(33)
VDCR usually gives only a minor duty cycle change, and has been omitted in the examples for simplicity.
SCHOTTKY DIODE CONDUCTION LOSSES
The conduction losses in the free-wheeling Schottky diode are calculated as follows:
PDIODE = VD1 x IOUT (1-D) (34)
Often this is the single most significant power loss in the circuit. Care should be taken to choose a Schottky
diode that has a low forward voltage drop.
INDUCTOR CONDUCTION LOSSES
Another significant external power loss is the conduction loss in the output inductor. The equation can be
simplified to:
PIND = IOUT2x RDCR (35)
MOSFET CONDUCTION LOSSES
The LMR12015/20 conduction loss is mainly associated with the internal NFET:
PCOND = IOUT2x RDSON x D (36)
MOSFET SWITCHING LOSSES
Switching losses are also associated with the internal NFET. They occur during the switch on and off transition
periods, where voltages and currents overlap resulting in power loss. The simplest means to determine this loss
is to empirically measuring the rise and fall times (10% to 90%) of the switch at the switch node:
PSWF = 1/2(VIN x IOUT x fSW x tFALL) (37)
PSWR = 1/2(VIN x IOUT x fSW x tRISE) (38)
PSW = PSWF + PSWR (39)
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 21
Product Folder Links: LMR12015 LMR12020
K = =
POUT
POUT + PLOSS
6.6 W
6.6 W + 1.499 W = 81 %
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
Table 1. Typical Rise and Fall Times vs Input Voltage
VIN tRISE tFALL
5V 8ns 8ns
10V 9ns 9ns
15V 10ns 10ns
IC QUIESCENT LOSSES
Another loss is the power required for operation of the internal circuitry:
PQ= IQx VIN (40)
IQis the quiescent operating current, and is typically around 2.4 mA.
MOSFET DRIVER LOSSES
The other operating power that needs to be calculated is that required to drive the internal NFET:
PBOOST = IBOOST x VBOOST (41)
VBOOST is normally between 3VDC and 5VDC. The IBOOST rms current is dependant on switching frequency fSW.
IBOOST is approximately 8.2 mA at 2 MHz and 4.4 mA at 1 MHz.
TOTAL POWER LOSSES
Total power losses are:
PLOSS = PCOND + PSWR + PSWF + PQ+ PBOOST + PDIODE + PIND (42)
Losses internal to the LMR12015/20 are:
PINTERNAL = PCOND + PSWR + PSWF + PQ+ PBOOST (43)
EFFICIENCY CALCULATION EXAMPLE
Operating conditions are:
VIN = 12V (44)
fSW = 2 MHz (45)
VOUT = 3.3V (46)
VD1 = 0.5V (47)
IOUT = 2A (48)
RDCR = 20 m(49)
Internal Power Losses are:
PCOND = IOUT2x RDSON x D= 22x 0.15x 0.314 = 188 mW (50)
PSW = (VIN x IOUT x fSW x tFALL) = (12V x 2A x 2 MHz x 10ns) = 480 mW (51)
PQ= IQx VIN = 2.4 mA x 12V = 29 mW (52)
PBOOST = IBOOST x VBOOST = 8.2 mA x 4.5V = 37mW (53)
PINTERNAL = PCOND + PSW + PQ+ PBOOST = 733 mW (54)
Total Power Losses are:
PDIODE= VD1 x IOUT (1 - D)= 0.5V x 2 x (1 - 0.314) = 686 mW (55)
PIND= IOUT2x RDCR= 22x 20 m= 80 mW (56)
PLOSS = PINTERNAL + PDIODE + P IND = 1.499 W (57)
The efficiency can now be estimated as:
(58)
With this information we can estimate the junction temperature of the LMR12015/20.
22 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
RTJA = TJ - TA
Power
RT = 'T
Power
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
CALCULATING THE LMR12015/20 JUNCTION TEMPERATURE
Thermal Definitions:
TJ= IC junction temperature
TA= Ambient temperature
RθJC = Thermal resistance from IC junction to device case
RθJA = Thermal resistance from IC junction to ambient air
Figure 34. Cross-Sectional View of Integrated Circuit Mounted on a Printed Circuit Board.
Heat in the LMR12015/20 due to internal power dissipation is removed through conduction and/or convection.
Conduction: Heat transfer occurs through cross sectional areas of material. Depending on the material, the
transfer of heat can be considered to have poor to good thermal conductivity properties (insulator vs conductor).
Heat Transfer goes as:
SiliconLead FramePCB (59)
Convection: Heat transfer is by means of airflow. This could be from a fan or natural convection. Natural
convection occurs when air currents rise from the hot device to cooler air.
Thermal impedance is defined as:
(60)
Thermal impedance from the silicon junction to the ambient air is defined as:
(61)
This impedance can vary depending on the thermal properties of the PCB. This includes PCB size, weight of
copper used to route traces , the ground plane, and the number of layers within the PCB. The type and number
of thermal vias can also make a large difference in the thermal impedance. Thermal vias are necessary in most
applications. They conduct heat from the surface of the PCB to the ground plane. Six to nine thermal vias should
be placed under the exposed pad to the ground plane. Placing more than nine thermal vias results in only a
small reduction to RθJA for the same copper area. These vias should have 8 mil holes to avoid wicking solder
away from the DAP. See AN-1187 SNOA401and AN-1520 SNVA183 for more information on package thermal
performance.
To predict the silicon junction temperature for a given application, three methods can be used. The first is useful
before prototyping and the other two can more accurately predict the junction temperature within the application.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 23
Product Folder Links: LMR12015 LMR12020
RTJC = TJ - TC
Power
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
Method 1:
The first method predicts the junction temperature by extrapolating a best guess RθJA from the table or graph.
The tables and graph are for natural convection. The internal dissipation can be calculated using the efficiency
calculations. This allows the user to make a rough prediction of the junction temperature in their application.
Methods two and three can later be used to determine the junction temperature more accurately.
The table below has values of RθJA for the WSON package.
Table 2. RθJA values for the LLP @ 1 Watt dissipation:
Number of Board Size of Bottom Layer Copper Size of Top Layer Copper Number of 8 mil RθJA
Layers Connected to DAP Connected to Dap Thermal Vias
2 0.25 in20.05 in28 78 °C/W
2 0.5625 in20.05 in28 65.6 °C/W
2 1 in20.05 in28 58.6 °C/W
2 1.3225 in20.05 in28 50 °C/W
4 (Eval Board) 3.25 in22.25 in215 30.7 °C/W
Figure 35. Estimate of Thermal Resistance vs. Ground Copper Area
Eight Thermal Vias and Natural Convection
Method 2:
The second method requires the user to know the thermal impedance of the silicon junction to case. (RθJC) is
approximately 9.1°C/W for the WSON. The case temperature should be measured on the bottom of the PCB at a
thermal via directly under the DAP of the LMR12015/20. The solder resist should be removed from this area for
temperature testing. The reading will be more accurate if it is taken midway between pins 2 and 9, where the
NMOS switch is located. Knowing the internal dissipation from the efficiency calculation given previously, and the
case temperature (TC) we have:
(62)
Therefore:
TJ= (RθJC x PLOSS) + TC(63)
24 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
+
-
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
PCB Layout Considerations
COMPACT LAYOUT
The performance of any switching converter depends as much upon the layout of the PCB as the component
selection. The following guidelines will help the user design a circuit with maximum rejection of outside EMI and
minimum generation of unwanted EMI.
Parasitic inductance can be reduced by keeping the power path components close together and keeping the
area of the loops small, on which high currents travel. Short, thick traces or copper pours (shapes) are best. In
particular, the switch node (where L1, D1, and the SW pin connect) should be just large enough to connect all
three components without excessive heating from the current it carries. The LMR12015/20 operates in two
distinct cycles (see Figure 27) whose high current paths are shown below in Figure 36:
Figure 36. Buck Converter Current Loops
The dark grey, inner loop represents the high current path during the MOSFET on-time. The light grey, outer loop
represents the high current path during the off-time.
GROUND PLANE AND SHAPE ROUTING
The diagram of Figure 36 is also useful for analyzing the flow of continuous current vs. the flow of pulsating
currents. The circuit paths with current flow during both the on-time and off-time are considered to be continuous
current, while those that carry current during the on-time or off-time only are pulsating currents. Preference in
routing should be given to the pulsating current paths, as these are the portions of the circuit most likely to emit
EMI. The ground plane of a PCB is a conductor and return path, and it is susceptible to noise injection just like
any other circuit path. The path between the input source and the input capacitor and the path between the catch
diode and the load are examples of continuous current paths. In contrast, the path between the catch diode and
the input capacitor carries a large pulsating current. This path should be routed with a short, thick shape,
preferably on the component side of the PCB. Multiple vias in parallel should be used right at the pad of the input
capacitor to connect the component side shapes to the ground plane. A second pulsating current loop that is
often ignored is the gate drive loop formed by the SW and BOOST pins and boost capacitor CBOOST. To minimize
this loop and the EMI it generates, keep CBOOST close to the SW and BOOST pins.
FB LOOP
The FB pin is a high-impedance input, and the loop created by R2, the FB pin and ground should be made as
small as possible to maximize noise rejection. R2 should therefore be placed as close as possible to the FB and
GND pins of the IC.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 25
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
PCB SUMMARY
1. Minimize the parasitic inductance by keeping the power path components close together and keeping the
area of the high-current loops small.
2. The most important consideration when completing the layout is the close coupling of the GND connections
of the CIN capacitor and the catch diode D1. These ground connections should be immediately adjacent, with
multiple vias in parallel at the pad of the input capacitor connected to GND. Place CIN and D1 as close to the
IC as possible.
3. Next in importance is the location of the GND connection of the COUT capacitor, which should be near the
GND connections of CIN and D1.
4. There should be a continuous ground plane on the copper layer directly beneath the converter. This will
reduce parasitic inductance and EMI.
5. The FB pin is a high impedance node and care should be taken to make the FB trace short to avoid noise
pickup and inaccurate regulation. The feedback resistors should be placed as close as possible to the IC,
with the GND of R2 placed as close as possible to the GND of the IC. The VOUT trace to R1 should be routed
away from the inductor and any other traces that are switching.
6. High AC currents flow through the VIN, SW and VOUT traces, so they should be as short and wide as
possible. However, making the traces wide increases radiated noise, so the layout designer must make this
trade-off. Radiated noise can be decreased by choosing a shielded inductor.
The remaining components should also be placed as close as possible to the IC. Please see Application Note
AN-2279 SNVU191 for further considerations and the LMR12015/20 eval board as an example of a four-layer
layout.
26 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND / DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
CLK
2 MHz
ON
OFF
C5
C4
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
LMR12015/20 Circuit Examples
Figure 37. VIN = 7 - 20V, VOUT = 5V, fSW = 2 MHz, IOUT = Full Load with CFF
Table 3. Bill of Materials for Figure 37
Part Name Part ID Part Value Part Number Manufacturer
Buck Regulator U1 1.5 or 2A Buck Regulator LMR12015/20 Texas Instruments
CPVIN C1 10 µF C1210C106K8PACTU Kemet
CBOOST C2 0.1 µF C0603X104K4RACTU Kemet
COUT C3 22 µF GRM32ER71C226KE18L MuRata
COUT C4 22 µF GRM32ER71C226KE18L MuRata
CFF C5 0.18 µF 0603ZC184KAT2A AVX
Catch Diode D1 Schottky Diode Vf = 0.32V CMS06 Toshiba
Inductor L1 3.3 µH 7447789003 Wurth
Feedback Resistor R1 4.02 kCRCW06034K02FKEA Vishay
Feedback Resistor R2 1.02 kCRCW06031K02FKEA Vishay
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 27
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND / DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
CLK
2 MHz
ON
OFF
C5
C4
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
Figure 38. VIN = 5 - 20V, VOUT = 3.3V, fSW = 2 MHz, IOUT = Full Load with CFF
Table 4. Bill of Materials for Figure 38
Part Name Part ID Part Value Part Number Manufacturer
Buck Regulator U1 1.5 or 2A Buck Regulator LMR12015/20 Texas Instruments
CPVIN C1 10 µF C1210C106K8PACTU Kemet
CBOOST C2 0.1 µF C0603X104K4RACTU Kemet
COUT C3 22 µF GRM32ER71C226KE18L MuRata
COUT C4 22 µF GRM32ER71C226KE18L MuRata
CFF C5 0.18 µF 0603ZC184KAT2A AVX
Catch Diode D1 Schottky Diode Vf = 0.32V CMS06 Toshiba
Inductor L1 3.3 µH 7447789003 Wurth
Feedback Resistor R1 2.32 kCRCW06032K32FKEA Vishay
Feedback Resistor R2 1.02 kCRCW06031K02FKEA Vishay
28 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND / DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
C4
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
Figure 39. VIN = 5 - 20V, VOUT = 3.3V, fSW = 2 MHz, IOUT = Full Load without CFF
Table 5. Bill of Materials for Figure 39
Part Name Part ID Part Value Part Number Manufacturer
Buck Regulator U1 1.5 or 2A Buck Regulator LMR12015/20 Texas Instruments
CPVIN C1 10 µF C1210C106K8PACTU Kemet
CBOOST C2 0.1 µF C0603X104K4RACTU Kemet
COUT C3 22 µF GRM32ER71C226KE18L MuRata
COUT C4 22 µF GRM32ER71C226KE18L MuRata
Catch Diode D1 Schottky Diode Vf = 0.32V CMS06 Toshiba
Inductor L1 3.3 µH 7447789003 Sumida
Feedback Resistor R1 2.32 kCRCW06032K32FKEA Vishay
Feedback Resistor R2 1.02 kCRCW06031K02FKEA Vishay
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 29
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND / DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
C4
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
Figure 40. VIN = 3.3 - 16V, VOUT = 1.8V, fSW = 2 MHz, IOUT = Full Load
Table 6. Bill of Materials for Figure 40
Part Name Part ID Part Value Part Number Manufacturer
Buck Regulator U1 1.5 or 2A Buck Regulator LMR12015/20 Texas Instruments
CPVIN C1 10 µF GRM32DR71E106KA12L Murata
CBOOST C2 0.1 µF GRM188R71C104KA01D Murata
COUT C3 22 µF C3225X7R1C226K TDK
COUT C4 22 µF C3225X7R1C226K TDK
Catch Diode D1 Schottky Diode Vf = 0.32V CMS06 Toshiba
Inductor L1 1.0 µH CDRH5D18BHPNP Sumida
Feedback Resistor R1 12 kCRCW060312K0FKEA Vishay
Feedback Resistor R2 15 kCRCW060315K0FKEA Vishay
30 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND / DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
CLK
1 MHz
ON
OFF
C5
C4
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
Figure 41. VIN = 3.3 - 16V, VOUT = 1.8V, fSW = 1 MHz, IOUT = Full Load
Table 7. Bill of Materials for Figure 41
Part Name Part ID Part Value Part Number Manufacturer
Buck Regulator U1 1.5 or 2A Buck Regulator LMR12015/20 Texas Instruments
CPVIN C1 10 µF GRM32DR71E106KA12L Murata
CBOOST C2 0.1 µF GRM188R71C104KA01D Murata
COUT C3 22 uF C3225X7R1C226K TDK
COUT C4 22 uF C3225X7R1C226K TDK
CFF C5 3.9 nF GRM188R71H392KA01D Murata
Catch Diode D1 Schottky Diode Vf = 0.32V CMS06 Toshiba
Inductor L1 1.8 µH CDRH5D18BHPNP Sumida
Feedback Resistor R1 12 kCRCW060312K0FKEA Vishay
Feedback Resistor R2 15 kCRCW060315K0FKEA Vishay
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 31
Product Folder Links: LMR12015 LMR12020
LMR12015/20
VIN PVIN
EN
BOOST
SW
FB
GND / DAP
VOUT
C2 L1
C1
C3
R1
R2
D1
SYNC
AVIN
CLK
2 MHz
ON
OFF
C5
C4
LMR12015, LMR12020
SNVS817A JUNE 2012REVISED APRIL 2013
www.ti.com
Figure 42. VIN = 3.3 - 9V, VOUT = 1.2V, fSW = 2 MHz, IOUT = Full Load
Table 8. Bill of Materials for Figure 42
Part Name Part ID Part Value Part Number Manufacturer
Buck Regulator U1 1.5 or 2A Buck Regulator LMR12015/20 Texas Instruments
CPVIN C1 10 µF GRM32DR71E106KA12L Murata
CBOOST C2 0.1 µF GRM188R71C104KA01D Murata
COUT C3 47 µF GRM32ER61A476KE20L Murata
COUT C4 22 µF C3225X7R1C226K TDK
CFF C5 NOT MOUNTED
Catch Diode D1 Schottky Diode Vf = 0.32V CMS06 Toshiba
Inductor L1 0.56 µH CDRH2D18/HPNP Sumida
Feedback Resistor R1 1.02 kCRCW06031K02FKEA Vishay
Feedback Resistor R2 5.10 kCRCW06035K10FKEA Vishay
32 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: LMR12015 LMR12020
LMR12015, LMR12020
www.ti.com
SNVS817A JUNE 2012REVISED APRIL 2013
REVISION HISTORY
Changes from Original (April 2013) to Revision A Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 32
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 33
Product Folder Links: LMR12015 LMR12020
PACKAGE OPTION ADDENDUM
www.ti.com 28-Sep-2016
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LMR12015XSD/NOPB ACTIVE WSON DSC 10 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 L285B
LMR12015XSDX/NOPB ACTIVE WSON DSC 10 4500 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 L285B
LMR12020XSD/NOPB ACTIVE WSON DSC 10 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 L284B
LMR12020XSDX/NOPB ACTIVE WSON DSC 10 4500 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 L284B
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
PACKAGE OPTION ADDENDUM
www.ti.com 28-Sep-2016
Addendum-Page 2
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LMR12015XSD/NOPB WSON DSC 10 1000 178.0 12.4 3.3 3.3 1.0 8.0 12.0 Q1
LMR12015XSDX/NOPB WSON DSC 10 4500 330.0 12.4 3.3 3.3 1.0 8.0 12.0 Q1
LMR12020XSD/NOPB WSON DSC 10 1000 178.0 12.4 3.3 3.3 1.0 8.0 12.0 Q1
LMR12020XSDX/NOPB WSON DSC 10 4500 330.0 12.4 3.3 3.3 1.0 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 8-Apr-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LMR12015XSD/NOPB WSON DSC 10 1000 210.0 185.0 35.0
LMR12015XSDX/NOPB WSON DSC 10 4500 367.0 367.0 35.0
LMR12020XSD/NOPB WSON DSC 10 1000 210.0 185.0 35.0
LMR12020XSDX/NOPB WSON DSC 10 4500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 8-Apr-2013
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
1.2±0.1
10X 0.3
0.2
10X 0.5
0.4
0.8 MAX
0.05
0.00
2±0.1
2X
2
8X 0.5
A
3.1
2.9
B3.1
2.9
(0.2) TYP
WSON - 0.8 mm max heightDSC0010B
PLASTIC SMALL OUTLINE - NO LEAD
4214926/A 07/2014
PIN 1 INDEX AREA
0.08 SEATING PLANE
(OPTIONAL)
PIN 1 ID
1
6
10
5
0.1 C A B
0.05 C
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.
0.08
0.1 C A B
0.05 C
SCALE 4.000
www.ti.com
EXAMPLE BOARD LAYOUT
0.07 MIN
ALL AROUND
0.07 MAX
ALL AROUND
(1.2)
(2)
10X (0.65)
10X (0.25)
(0.35) TYP
(0.75) TYP
(2.75)
() TYP
VIA
0.2
8X (0.5)
WSON - 0.8 mm max heightDSC0010B
PLASTIC SMALL OUTLINE - NO LEAD
4214926/A 07/2014
SYMM
SYMM
LAND PATTERN EXAMPLE
SCALE:20X
1
56
10
NOTES: (continued)
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
number SLUA271 (www.ti.com/lit/slua271).
SOLDER MASK
OPENING
METAL
UNDER
SOLDER MASK
SOLDER MASK
DEFINED
METAL
SOLDER MASK
OPENING
SOLDER MASK DETAILS
NON SOLDER MASK
DEFINED
(PREFERRED)
www.ti.com
EXAMPLE STENCIL DESIGN
(1.13)
(0.89)
10X (0.65)
10X (0.25)
8X (0.5)
(2.75)
(0.55)
WSON - 0.8 mm max heightDSC0010B
PLASTIC SMALL OUTLINE - NO LEAD
4214926/A 07/2014
NOTES: (continued)
5. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
SYMM
SYMM
METAL
TYP
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
EXPOSED PAD
84% PRINTED SOLDER COVERAGE BY AREA
SCALE:25X
IMPORTANT NOTICE
Texas Instruments Incorporated (TI) reserves the right to make corrections, enhancements, improvements and other changes to its
semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers
should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
TI’s published terms of sale for semiconductor products (http://www.ti.com/sc/docs/stdterms.htm) apply to the sale of packaged integrated
circuit products that TI has qualified and released to market. Additional terms may apply to the use or sale of other types of TI products and
services.
Reproduction of significant portions of TI information in TI data sheets is permissible only if reproduction is without alteration and is
accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such reproduced
documentation. Information of third parties may be subject to additional restrictions. Resale of TI products or services with statements
different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the
associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Buyers and others who are developing systems that incorporate TI products (collectively, “Designers”) understand and agree that Designers
remain responsible for using their independent analysis, evaluation and judgment in designing their applications and that Designers have
full and exclusive responsibility to assure the safety of Designers' applications and compliance of their applications (and of all TI products
used in or for Designers’ applications) with all applicable regulations, laws and other applicable requirements. Designer represents that, with
respect to their applications, Designer has all the necessary expertise to create and implement safeguards that (1) anticipate dangerous
consequences of failures, (2) monitor failures and their consequences, and (3) lessen the likelihood of failures that might cause harm and
take appropriate actions. Designer agrees that prior to using or distributing any applications that include TI products, Designer will
thoroughly test such applications and the functionality of such TI products as used in such applications.
TI’s provision of technical, application or other design advice, quality characterization, reliability data or other services or information,
including, but not limited to, reference designs and materials relating to evaluation modules, (collectively, “TI Resources”) are intended to
assist designers who are developing applications that incorporate TI products; by downloading, accessing or using TI Resources in any
way, Designer (individually or, if Designer is acting on behalf of a company, Designer’s company) agrees to use any particular TI Resource
solely for this purpose and subject to the terms of this Notice.
TI’s provision of TI Resources does not expand or otherwise alter TI’s applicable published warranties or warranty disclaimers for TI
products, and no additional obligations or liabilities arise from TI providing such TI Resources. TI reserves the right to make corrections,
enhancements, improvements and other changes to its TI Resources. TI has not conducted any testing other than that specifically
described in the published documentation for a particular TI Resource.
Designer is authorized to use, copy and modify any individual TI Resource only in connection with the development of applications that
include the TI product(s) identified in such TI Resource. NO OTHER LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE
TO ANY OTHER TI INTELLECTUAL PROPERTY RIGHT, AND NO LICENSE TO ANY TECHNOLOGY OR INTELLECTUAL PROPERTY
RIGHT OF TI OR ANY THIRD PARTY IS GRANTED HEREIN, including but not limited to any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
regarding or referencing third-party products or services does not constitute a license to use such products or services, or a warranty or
endorsement thereof. Use of TI Resources may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
TI RESOURCES ARE PROVIDED “AS IS” AND WITH ALL FAULTS. TI DISCLAIMS ALL OTHER WARRANTIES OR
REPRESENTATIONS, EXPRESS OR IMPLIED, REGARDING RESOURCES OR USE THEREOF, INCLUDING BUT NOT LIMITED TO
ACCURACY OR COMPLETENESS, TITLE, ANY EPIDEMIC FAILURE WARRANTY AND ANY IMPLIED WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF ANY THIRD PARTY INTELLECTUAL
PROPERTY RIGHTS. TI SHALL NOT BE LIABLE FOR AND SHALL NOT DEFEND OR INDEMNIFY DESIGNER AGAINST ANY CLAIM,
INCLUDING BUT NOT LIMITED TO ANY INFRINGEMENT CLAIM THAT RELATES TO OR IS BASED ON ANY COMBINATION OF
PRODUCTS EVEN IF DESCRIBED IN TI RESOURCES OR OTHERWISE. IN NO EVENT SHALL TI BE LIABLE FOR ANY ACTUAL,
DIRECT, SPECIAL, COLLATERAL, INDIRECT, PUNITIVE, INCIDENTAL, CONSEQUENTIAL OR EXEMPLARY DAMAGES IN
CONNECTION WITH OR ARISING OUT OF TI RESOURCES OR USE THEREOF, AND REGARDLESS OF WHETHER TI HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Unless TI has explicitly designated an individual product as meeting the requirements of a particular industry standard (e.g., ISO/TS 16949
and ISO 26262), TI is not responsible for any failure to meet such industry standard requirements.
Where TI specifically promotes products as facilitating functional safety or as compliant with industry functional safety standards, such
products are intended to help enable customers to design and create their own applications that meet applicable functional safety standards
and requirements. Using products in an application does not by itself establish any safety features in the application. Designers must
ensure compliance with safety-related requirements and standards applicable to their applications. Designer may not use any TI products in
life-critical medical equipment unless authorized officers of the parties have executed a special contract specifically governing such use.
Life-critical medical equipment is medical equipment where failure of such equipment would cause serious bodily injury or death (e.g., life
support, pacemakers, defibrillators, heart pumps, neurostimulators, and implantables). Such equipment includes, without limitation, all
medical devices identified by the U.S. Food and Drug Administration as Class III devices and equivalent classifications outside the U.S.
TI may expressly designate certain products as completing a particular qualification (e.g., Q100, Military Grade, or Enhanced Product).
Designers agree that it has the necessary expertise to select the product with the appropriate qualification designation for their applications
and that proper product selection is at Designers’ own risk. Designers are solely responsible for compliance with all legal and regulatory
requirements in connection with such selection.
Designer will fully indemnify TI and its representatives against any damages, costs, losses, and/or liabilities arising out of Designer’s non-
compliance with the terms and provisions of this Notice.
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2018, Texas Instruments Incorporated
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Texas Instruments:
LMR12015XSD/NOPB LMR12015XSDX/NOPB