1
3
4
5
6
2
7
EP
LED+
LED+
DIM
GND
VREF
IADJ
LED-
VIN High Power LED String
ILED
CIN
IIN
TPS92550
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
TPS92550 450mA 14W Constant Current Buck LED Driver Micro-Module
Check for Samples: TPS92550
1FEATURES DESCRIPTION
The TPS92550 Constant Current Buck LED Driver
2• Integrated all Power Components Including Micro-Module drives maximum 450mA LED current
the Power Inductor up to 10 LEDs in a single string (maximum 14W). It
• Wide Input Voltage Range : 4.5V–36V integrates all the power components including the
• Constant Switching Frequency at 400kHz power inductor. The TPS92550 provides a full turn-
key, highly efficient solution for wide range of single
• High Contrast Ratio (Minimum dimming string LED lighting applications with up to 96% power
current pulse width < 16µs) efficiency. It accepts an input voltage ranging from
• Drives up to 10 LEDs in Series at 36V Input 4.5V to 36V and delivers a 350mA LED current as
• ±3.6% Typical LED Current Accuracy default. The LED current is adjustable from 300mA to
450mA by changing a single external resistor.
• LED Current Adjustable from 300mA to 450mA The module operates at constant switching frequency
• Up to 96% Efficiency (400kHz) with low Electro Magnetic Interference
• TPS92550 Modules can be Connected in (EMI) complying with EN55015 standard. The module
Parallel for Higher Current Operation has fast control loop to realize fine LED current pulse
• Input Under-Voltage Lock-Out (UVLO) yielding 256–step PWM dimming resolution at 240Hz
for general lighting. Protection feature include thermal
• Compatible with Ceramic and Low ESR shutdown, input under-voltage lockout, LED open-
Capacitors circuit and short-circuit protections. The TPS92550
• Low Electro Magnetic Interference(EMI) Micro-Module is available in 7-pin PFM power
Complies with EN55015 Standard (1) package.
• LED Open and Short Circuit Protections
• Thermal Shutdown and RoHS Compliant
• –40°C to +125˚C Junction Temperature Range
APPLICATIONS
• General Lighting, Desk Lamps
– Cabinet Lamps, Decorative Lamps
– Street Lamps
• Architecture Lighting, Recess Lights
– Spot Lights
– Underwater Lights
PACKAGE HIGHLIGHTS
• 7 Lead Easy-to-use Package (Similar to TO-
263)
• Single Exposed Die Attach Pad for Enhancing
Thermal Performance
• 10.2 x 13.8 x 4.6 mm Package Figure 1. Typical Application Circuit
(1) EN55015, refer to Figure 36 and Figure 37
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.
2All 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.
20 24 28 32 36
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
6LED 8LED 10LED
4 s/DIV
ILED(200mA/DIV)
VDIM(2V/DIV)
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
SYSTEM PERFORMANCE
Figure 2. Efficiency vs VIN , ILED = 350mA Figure 3. LED Current with PWM Dimming
16µs Dimming Pulse
Figure 4. Radiated Emissions (EN 55015)
Easy to Use 7-Pin Package
(1) θJA measured on a 1.705” x 3.0” four layer board, with one ounce copper , thirty five 12 mil thermal vias, no air flow,
and 1W power dissipation.
Figure 5. 7-Pin PFM Package
10.16 x 13.77 x 4.57 mm (0.4 x 0.39 x 0.18 in)
θJA = 20°C/W, θJC = 1.9°C/W(1)
RoHS Compliant
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Product Folder Links: TPS92550
1
3
4
5
6
2
7
Exposed Pad
Connect to GND
LED+
LED+
DIM
GND
VREF
IADJ
LED-
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
CONNECTION DIAGRAM
Figure 6. 7-Pin PFM (Top View)
See NDW0007A Package
PIN DESCRIPTIONS
Pin Name Description Function
Number
1,2 LED+ Anode of LED string Supply input and rail connection to the anode of the LED string.
3 DIM Dimming signal input Dimming control signal input. Open to enable or apply logic level PWM signal
to control the brightness of the LED string.
4 GND Ground Reference point for all stated voltages. Connect to the exposed pad of the
package externally.
5 VREF Voltage reference Internal voltage reference output.
6 IADJ LED current adjustment Fine tunning of the LED current by connecting a resistor between this pin and
ground. Connect this pin to ground for factory preset current.
7 LED- Cathode of LED string The current return pin of the LED string, connect to the cathode of the LED
string.
EP Exposed Pad Exposed thermal pad Used to dissipate heat from the package during operation. Must connect to
GND directly.
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TPS92550
SNVS806C –MAY 2012–REVISED MAY 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)
VALUE / UNITS
LED+, LED- to GND -0.3V to 40V
DIM to GND -0.3V to 6V
IADJ, VREF to GND -0.3V to 5V
ESD Susceptibility (2) ±2 kV (All pins Except Pin 6)
Power Dissipation Internally Limited
Junction Temperature 150°C
Storage Temperature Range 0°C to 150°C
Peak Reflow Case Temperature (30 sec) 245°C
(1) Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which
operation of the device is intended to be functional. For specifications and test conditions, see the Electrical Characteristics.
(2) The human body model is a 100 pF capacitor discharged through a 1.5 kΩresistor into each pin. The Pin 6 ( IADJ pin) pass ± 1kV.Test
method is per JESD22-AI14S.
RECOMMENDED OPERATING CONDITIONS (1)
VALUE / UNITS
LED+, LED- 4.5V to 36V
DIM 0V to 5.5V
IADJ 0V to 0.2V
Junction Temperature (TJ) –40°C to 125°C
(1) Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which
operation of the device is intended to be functional. For specifications and test conditions, see the Electrical Characteristics.
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TPS92550
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SNVS806C –MAY 2012–REVISED MAY 2013
ELECTRICAL CHARACTERISTICS
Limits in standard type are for TJ= 25°C unless otherwise stated; limits in boldface type apply over the operating junction
temperature range TJof –40°C to 125°C. Minimum and maximum limits are specified through test, design, or statistical
correlation. Typical values represent the most likely parametric norm at TJ= 25°C, and are provided for reference purposes
only. Unless otherwise stated the following conditions apply: VIN =24 V, ILED = 350mA. VIN is the voltage applied across LED+
and GND. IIN is the input current flowing into the LED+ node. ILED is a LED current flowing into the LED- pin. VLED is the
voltage applied across LED+ and LED-. VDIM is the voltage applied across the DIM pin to ground. Resistor RIADJ connect from
IADJ pin to ground. Resistor RVREF connect from VREF pin to ground.
Symbol Parameter Conditions Min (1) Typ (2) Max (1) Units
SYSTEM PARAMETERS
IIN Input Current VLED = 0V, 4.5V ≤VIN ≤36V, VDIM = 0V 2.0 2.35 2.7 mA
ILED LED Current VLED = 18V, RIADJ = 0Ω, RVREF = open, TJ= 25°C 336 350 361 mA
VLED = 18V, RIADJ = 0Ω, RVREF = open, 328 350 361
TJ= 25°C to 125°C
VLED = 18V, RIADJ = 0Ω, RVREF = open, 328 350 370
TJ= –40°C to 125°C
ILED–36V LED Current at VIN = 36V VIN = 36V, VLED = 24V, RIADJ = 0Ω, RVREF = open, 332 350 359 mA
TJ= 25°C
VIN = 36V, VLED = 24V, RIADJ = 0Ω, RVREF = open, 330 350 359
TJ= 25°C to 125°C
VIN = 36V, VLED = 24V, RIADJ = 0Ω, RVREF = open, 330 350 366
TJ= –40°C to 125°C
ILED-ADJ1 Adjusted LED Current VLED = 18V, RIADJ = 0Ω, RVREF = 10.5kΩ, TJ= 25°C 432 450 466 mA
VLED = 18V, RIADJ = 0Ω, RVREF = 10.5kΩ, 429 450 466
TJ= 25°C to 125°C
VLED = 18, V RIADJ = 0Ω, RVREF = 10.5kΩ,429 450 474
TJ= –40°C to 125°C
ILED-ADJ2 Adjusted LED Current VLED = 18V, RIADJ = 500Ω, RVREF = open, 287 300 309 mA
TJ= 25°C
VLED = 18V, RIADJ = 500Ω, RVREF = open, 283 300 309
TJ= 25°C to 125°C
VLED = 18V, RIADJ = 500Ω, RVREF = open, 283 300 315
TJ= –40°C to 125°C
ILED-SHORT LED Short Circuit Current VLED = 0V, VIN = 36V, DIM = open 800 900 1020 mA
at VIN = 36V
ILED-LEAK “LED-” pin leakage VLED = 0V, VIN = operating max, DIM = 0V 1.2 µA
current
fSW Switching Frequency VLED = 12V, RIADJ = 0Ω, RVREF = open 365 400 450 kHz
VDIM DIM Pin Threshold VDIM Increasing 1.0 1.2 V
VDIM-HYS DIM Pin Hysteresis 0.25 V
THERMAL CHARACTERISTICS
TSD Thermal Shutdown TJRising 170 °C
Temperature
TSD-HYS Thermal Shutdown Temp. TJRising 10 °C
Hysteresis
θJA Junction to Ambient(3) 4 Layer JEDEC Printed Circuit Board, 100 vias, No air flow 19.3 °C/W
2 Layer JEDEC PCB, No air flow 21.5
θJC Junction to Case No air flow 1.9 °C/W
(1) Min and Max limits are 100% production tested at an ambient temperature (TA) of 25°C. Limits over the operating temperature range are
specified through correlation using Statistical Quality Control (SQC) methods. Limits are used to calculate Average Outgoing Quality
Level (AOQL).
(2) Typical numbers are at 25°C and represent the most likely parametric norm.
(3) θJA measured on a 1.705” x 3.0” four layer board, with one ounce copper , thirty five 12 mil thermal vias, no air flow, and 1W power
dissipation.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: TPS92550
0 4 8 12 16 20 24 28 32 36
60
65
70
75
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
1LED
2LED
3LED 4LED
0 4 8 12 16 20 24 28 32 36
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
VIN(V)
1LED
2LED
3LED 4LED
20 24 28 32 36
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
6LED 8LED 10LED
20 24 28 32 36
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
VIN(V)
6LED
8LED 10LED
0 4 8 12 16 20 24 28 32 36
60
65
70
75
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
1LED
2LED
3LED 4LED
0 4 8 12 16 20 24 28 32 36
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
VIN(V)
1LED
2LED 3LED
4LED
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS
Unless otherwise specified, the following conditions apply: VIN = 24V, CIN is a 2.2µF 100V X7R ceramic capacitor for driving
2–7 power LEDs with ILED = 350mA. Single LED forward voltage used is 3.2V. TA= 25°C for efficiency curves and waveforms.
Efficiency vs ILED Regulation vs
VIN, ILED = 350mA VIN, ILED = 350mA
Figure 7. Figure 8.
Efficiency vs ILED Regulation vs
VIN, ILED = 350mA VIN, ILED = 350mA
Figure 9. Figure 10.
Efficiency vs ILED Regulation vs
VIN, ILED = 450mA VIN, ILED = 450mA
Figure 11. Figure 12.
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20 24 28 32 36
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
6LED 8LED 10LED
20 24 28 32 36
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
VIN(V)
6LED 8LED
10LED
0 4 8 12 16 20 24 28 32 36
60
65
70
75
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
1LED
2LED
3LED 4LED
0 4 8 12 16 20 24 28 32 36
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
VIN(V)
1LED
2LED 3LED
4LED
20 24 28 32 36
80
85
90
95
100
EFFICIENCY (%)
VIN(V)
6LED 8LED 10LED
20 24 28 32 36
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
VIN(V)
6LED 8LED 10LED
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V, CIN is a 2.2µF 100V X7R ceramic capacitor for driving
2–7 power LEDs with ILED = 350mA. Single LED forward voltage used is 3.2V. TA= 25°C for efficiency curves and waveforms.
Efficiency vs ILED Regulation vs
VIN, ILED = 450mA VIN, ILED = 450mA
Figure 13. Figure 14.
Efficiency vs ILED Regulation vs
VIN, ILED = 300mA VIN, ILED = 300mA
Figure 15. Figure 16.
Efficiency vs ILED Regulation vs
VIN, ILED = 300mA VIN, ILED = 300mA
Figure 17. Figure 18.
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0 4 8 12 16 20 24 28 32 36
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
IIN(mA)
VIN(V)
TJ=25°C
TJ=-40°C TJ=125°C
0 4 8 12 16 20 24 28 32 36
0
50
100
150
200
250
300
350
400
450
ILED(mA)
VIN(V)
TJ=25°C
TJ=-40°C
TJ=125°C
4 s/DIV
ILED(200mA/DIV)
VDIM(2V/DIV)
0 4 8 12 16 20 24 28 32 36
0.0
0.5
1.0
1.5
2.0
2.5
3.0
IIN(mA)
VIN(V)
TJ=25°C
TJ=-40°C
TJ=125°C
2 s/DIV
ILED(200mA/DIV)
VDIM(2V/DIV)
2 s/DIV
ILED(200mA/DIV)
VDIM(2V/DIV)
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V, CIN is a 2.2µF 100V X7R ceramic capacitor for driving
2–7 power LEDs with ILED = 350mA. Single LED forward voltage used is 3.2V. TA= 25°C for efficiency curves and waveforms.
LED Current with PWM Dimming LED Current with PWM Dimming
VDIMRising VDIMFalling
Figure 19. Figure 20.
LED Current with PWM Dimming IIN vs VIN
16µs dimming pulse VDIM = 0V
Figure 21. Figure 22.
IIN vs VIN ILED vs VIN
LED = open , DIM = open 3LED
Figure 23. Figure 24.
8Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: TPS92550
8 12 16 20 24 28 32 36
-3
-2
-1
0
1
2
3
FREQUENCY DEVIATION (%)
VIN(V)
TJ=25°C
TJ=-40°C
TJ=125°C
-50 -25 0 25 50 75 100 125
-3
-2
-1
0
1
2
3
ILEDREGULATION (%)
TEMPERATURE (°C)
VIN=12V(2LED)
VIN=24V(4LED)
VIN=36V(6LED)
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
ILED(%)
DIM DUTY RATIO (%)
VIN=12V(2LED)
VIN=24V(4LED)
VIN=36V(6LED)
0.0 0.2 0.4 0.6 0.8 1.0
0.0
0.2
0.4
0.6
0.8
1.0
ILED(%)
DIM DUTY RATIO (%)
VIN=12V(2LED)
VIN=24V(4LED)
VIN=36V(6LED)
0 4 8 12 16 20 24 28 32 36
0
200
400
600
800
1000
ILED(mA)
VIN(V)
TJ=25°C
TJ=125°C
TJ=-40°C
0 4 8 12 16 20 24 28 32 36
0
20
40
60
80
100
IIN(mA)
VIN(V)
TJ=25°C
TJ=-40°C
TJ=125°C
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V, CIN is a 2.2µF 100V X7R ceramic capacitor for driving
2–7 power LEDs with ILED = 350mA. Single LED forward voltage used is 3.2V. TA= 25°C for efficiency curves and waveforms.
ILED vs VIN IIN vs VIN
VLED = 0V, DIM = open VLED = 0V, DIM = open
Figure 25. Figure 26.
ILED vs Dimming Duty Ratio ILED vs Dimming Duty Ratio
Figure 27. Figure 28.
Frequency Deviation vs VIN (400kHz) ILED Regulation vs Temperature
Figure 29. Figure 30.
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0 100 200 300 400 500
300
310
320
330
340
350
ILED(mA)
RIADJ()
0 20 40 60 80 100
350
375
400
425
450
ILED(mA)
RVREF(k)
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Unless otherwise specified, the following conditions apply: VIN = 24V, CIN is a 2.2µF 100V X7R ceramic capacitor for driving
2–7 power LEDs with ILED = 350mA. Single LED forward voltage used is 3.2V. TA= 25°C for efficiency curves and waveforms.
ILED vs RIADJ ILED vs RVREF
RVREF = open RIADJ = 0Ω
Figure 31. Figure 32.
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Product Folder Links: TPS92550
Voltage
Regulator
VCC
Switch
Control logic
VIN
VCC
-
+
1.2V
DIM
VREF
IADJ
LED-
LED+
GND
EP
4.5V to 36V
3 k
47 PH
1 PF
0.33 PFCIN
1,2
7
4
6
5
3
4
High power LED Array
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
BLOCK DIAGRAM
Operation Description
The TPS92550 is a high power floating buck LED driver with wide input voltage range. It requires no external
current sensing elements and loop compensation network. The integrated power switch enables high output
power up to 14W with 450mA LED current.
High speed dimming control input allows precision and high resolution brightness control for applications which
require fine brightness adjustment.
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Links: TPS92550
1
3
4
5
6
2
7
EP
LED+
LED+
DIM
GND
VREF
IADJ
LED-
VIN High Power LED String
ILED
IIN
TPS92550
CIN
RVREF
RIADJ
LED VREF
1050
I3k / /R
LED IADJ
1050
I3k R
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
APPLICATION INFORMATION
SETTING THE LED CURRENT
The TPS92550 requires no external current sensing resistor for LED current regulation. The average LED current
of the TPS92550 is adjustable from 300mA to 450mA by varying the resistance of the resistor according to the
following equation and table.
For RVREF = open and RIADJ <=499Ω
(1)
For RIADJ = 0 and RVREF >= 10.5kΩ
(2)
Table 1. Example for ILED Setting
RIADJ(Ω) RVREF(Ω) ILED(mA)
499 OPEN 300
SHORT OPEN 350
SHORT 10.5k 450
Figure 33. TPS92550 Application Schematic for ILED Setting
Minimum Switch On-Time
The on-time of the internal switch should be no shorter than 400ns. The number of LED (typical forward voltage
at 3.2V) to input voltage is constrained by that as shown in the following table.
No. of LED Max. VIN(V)
1 20
2 – 10 36
Peak Switch Current Limit
The TPS92550 features an integrated switch current limiting mechanism to prevent the LEDs from being over-
driven. The switch current limiter is triggered when the switch current is three times exceeding the current level
set by resistor. Once the current limiter is triggered, the internal power switch turn OFF for 3.6µs to discharge the
inductor until inductor current reduces back to normal level. The current limiting feature is exceptionally important
to avoid permanent damage of the TPS92550 application circuit due to short circuit of LED string.
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Product Folder Links: TPS92550
3
4
5
6
2
7
EP
VIN ILED
TPS92550
EP
High Power LED String
CIN
COUT
ILED2
ILED1 CIN
TPS92550
1
3
4
5
6
2
7
1
LED+
LED+
DIM
GND
VREF
IADJ
LED-
LED+
LED+
DIM
GND
VREF
IADJ
LED-
COUT
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
PWM Dimming Control
The DIM pin of the TPS92550 is an input with internal pull-up that accepts logic signals for average LED current
control. Applying a logic high (above 1.2V) signal to the DIM pin or leaving the DIM pin open will enable the
device. Applying a logic low signal (below 0.7V) to the DIM pin will disable the switching activity of the device but
maintain operation of the VCC regulator active. The TPS92550 operation of high speed dimming and very fine
dimming control as shown in Figure 34.
Figure 34. Shortened Current Slew up Time of the TPS92550
To ensure normal operation of the TPS92550, it is recommended to set the dimming frequency not higher than
1/10 of the switching frequency. The dim pulse on time is tested down to 16µs. In applications that require high
dimming contrast ratio, low dimming frequency should be used.
Parallel Operation
When a load current higher than 450mA is required by the application, TPS92550 can be used in parallel to
deliver higher current. With common VINs and GNDs, the TPS92550 will operate as independent asynchronous
current sinks driving the same LED load. The total DC current of the modules will be additive; however, low
frequency sub-harmonic current ripple may be present and its frequency and magnitude will depend upon the
phase relationship between the internal clocks as there is no provision for synchronizing driver clocks. It is
suggested to have minimum 2.2μF COUT located close to the module to filter out the current ripple, and the
resultant LED current will become DC. Current sharing modules should have a local CIN capacitor of minimum
2.2μF located as close to VIN and GND as possible. Refer to Figure 35 for the TPS92550 parallel operation
circuit schematic. Refer to Figure 36 for the TPS92550 parallel operation results ILED vs VIN.
Figure 35. Parallel Operation Circuit Schematic for ILED = 900mA
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LED+ LED-
TPS92550
GND
VIN
High power LED Array
CIN
COUT
Loop1
Loop 2 di/dt
0 10 20 30 40
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
ILED(A)
VIN(V)
1LED 5LED
10LED
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
Figure 36. Parallel Operation Results for ILED = 900mA, ILED vs VIN
PC Board Layout Considerations
The overall performance of the LED driver is highly depends on the PCB layout. Poor board layout can disrupt
the performance of the TPS92550 and surrounding circuitry by contributing to EMI, ground bounce and resistive
voltage drop in the traces. These can send erroneous signals to the LED driver resulting in poor regulation and
stability. Good layout can be implemented by following a few simple design rules.
1. Place CIN as close as possible to the VIN pin and GND exposed pad (EP).
2. Place COUT (optional for reduction of LED current ripple and EMI compliance) as close as possible to the
VLED+ pin and VLED- pin.
3. The exposed pad (EP) must connect to the GND pin directly.
EMI Design Considerations
From an EMI reduction standpoint, it is imperative to minimize the di/dt current paths (refer to Figure 37).
Therefore, it is essential to connect an 2.2µF capacitor (COUT) across the LED+ pin and LED- pin. This will
minimize the ripple current so that it can reduce radiated EMI (refer to Figure 38 and Figure 39).
Figure 37. Current Loops
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Product Folder Links: TPS92550
LED+ LED-
TPS92550
IADJ GND VREF
DIM
VIN
PWM
Dimming
Signal
CIN
2.2 PF
100V
High power LED Array
1,2
3
4,EP 56
7
COUT
2.2 PF 100V
U1
LED+ LED-
TPS92550
IADJ GND VREF
DIM
VIN
PWM
Dimming
Signal
CIN
2.2 PF
100V
High power LED Array
1,2
3
4,EP 56
7
U1
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
Figure 38. Complies with EN55015 Radiated Figure 39. Complies with EN55015 Radiated
Emissions (HORI. / HEIGHT=3.0m / RANGE=10m) Emissions (VERT. / HEIGHT=1.0m / RANGE=10m)
CIN = 2.2µF, COUT = 2.2uF, VIN = 36V, ILED = 350mA, CIN = 2.2µF, COUT = 2.2uF, VIN = 36V , ILED = 350mA,
No. of LED = 10 No. of LED = 10
TPS92550 Application Circuit Schematic and BOM
Table 2. Bill of Materials, VIN = 18V , ILED = 350mA, No. of LED = 2 — 5
Designator Description Case Size Manufacturer Manufacturer P/N Quantity
U1 LED Micro-Module Driver PFM Texas Instruments TPS92550TZ 1
CIN 2.2 µF, 100V, X7R 1210 Murata GRM32ER72A225KA35L 1
Table 3. Bill of Materials, VIN = 36V , ILED = 350mA , No.of LED = 10, Complies with EN55015 Radiated
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: TPS92550
TPS92550
SNVS806C –MAY 2012–REVISED MAY 2013
www.ti.com
Table 3. Bill of Materials, VIN = 36V , ILED = 350mA , No.of LED = 10, Complies with EN55015 Radiated
Emissions (continued)
Emissions
Designator Description Case Size Manufacturer Manufacturer P/N Quantity
U1 LED Micro-Module Driver PFM Texas Instruments TPS92550TZ 1
CIN 2.2 µF, 100V, X7R 1210 Murata GRM32ER72A225KA35L 1
COUT 2.2 µF, 100V, X7R 1210 Murata GRM32ER72A225KA35L 1
PCB Layout Diagrams
The PCB design is available in the TPS92550 product folder at www.ti.com.
Figure 40. Top Layer and Top Overlay
16 Submit Documentation Feedback Copyright © 2012–2013, Texas Instruments Incorporated
Product Folder Links: TPS92550
TPS92550
www.ti.com
SNVS806C –MAY 2012–REVISED MAY 2013
REVISION HISTORY
Changes from Revision B (May 2013) to Revision C Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 18
Copyright © 2012–2013, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: TPS92550
PACKAGE OPTION ADDENDUM
www.ti.com 27-Apr-2017
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
TPS92550TZ/NOPB ACTIVE TO-PMOD NDW 7 250 RoHS (In
Work) & Green
(In Work)
CU SN Level-3-245C-168 HR -40 to 125 TPS92550
TZ
TPS92550TZX/NOPB ACTIVE TO-PMOD NDW 7 500 RoHS (In
Work) & Green
(In Work)
CU SN Level-3-245C-168 HR -40 to 125 TPS92550
TZ
(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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(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.
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.
PACKAGE OPTION ADDENDUM
www.ti.com 27-Apr-2017
Addendum-Page 2
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
TPS92550TZ/NOPB TO-
PMOD NDW 7 250 330.0 24.4 10.6 14.22 5.0 16.0 24.0 Q2
TPS92550TZX/NOPB TO-
PMOD NDW 7 500 330.0 24.4 10.6 14.22 5.0 16.0 24.0 Q2
PACKAGE MATERIALS INFORMATION
www.ti.com 15-Apr-2016
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
TPS92550TZ/NOPB TO-PMOD NDW 7 250 367.0 367.0 45.0
TPS92550TZX/NOPB TO-PMOD NDW 7 500 367.0 367.0 45.0
PACKAGE MATERIALS INFORMATION
www.ti.com 15-Apr-2016
Pack Materials-Page 2
MECHANICAL DATA
NDW0007A
www.ti.com
TZA07A (Rev D)
TOP SIDE OF PACKAGE
BOTTOM SIDE OF PACKAGE
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