General Description
The LM4041 is a precision two-terminal shunt mode,
bandgap voltage reference with a fixed reverse break-
down voltage of 1.225V. Ideal for space-critical appli-
cations, the LM4041 is offered in the subminiature 3-pin
SC70 surface-mount package (1.8mm ✕1.8mm), 50%
smaller than comparable devices in SOT23 surface-
mount packages (SOT23 versions are also available).
Laser-trimmed resistors ensure precise initial accuracy.
With a 100ppm/°C temperature coefficient, the device
is offered in four grades of initial accuracy ranging from
0.1% to 1%. The LM4041 has a 60µA to 12mA shunt
current capability with low dynamic impedance, ensur-
ing stable reverse breakdown voltage accuracy over a
wide range of operating temperatures and currents.
The LM4041 does not require an external stabilizing
capacitor while ensuring stability with any capacitive
load.
________________________Applications
Portable, Battery-Powered Equipment
Notebook Computers
Cell Phones
Industrial Process Controls
Features
♦Ultra-Small 3-Pin SC70 Package
♦0.1% max Initial Accuracy
♦100ppm/°C max Temperature Coefficient
Guaranteed over -40°C to +85°C Temperature
Range
♦Wide Operating Current Range: 60µA to 12mA
♦Low 20µVRMS Output Noise (10Hz to 10kHz)
♦1.225V Fixed Reverse Breakdown Voltage
♦No Output Capacitors Required
♦Tolerates Capacitive Loads
LM4041
Improved Precision Micropower
Shunt Voltage Reference
________________________________________________________________ Maxim Integrated Products 1
-
1
3N.C.*
+
LM4041
SC70-3/SOT23-3
TOP VIEW
2
*PIN 3 MUST BE LEFT FLOATING
OR CONNECTED TO PIN 2.
PART
OUTPUT
VOLTAGE
(V)
INITIAL
ACCURACY
(%)
TEMPCO
(ppm/°C)
LM4041AIM3-1.2 1.225 0.1 100
LM4041AIX3-1.2 1.225 0.1 100
LM4041BIM3-1.2 1.225 0.2 100
LM4041BIX3-1.2 1.225 0.2 100
LM4041CIM3-1.2 1.225 0.5 100
LM4041CIX3-1.2 1.225 0.5 100
LM4041DIM3-1.2 1.225 1.0 150
LM4041DIX3-1.2 1.225 1.0 150
Pin Configuration Selector Guide
19-1704; Rev 0; 4/00
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Ordering Information
PART* TEMP.
RANGE
PIN-
PACKAGE
TOP
MARK
LM4041AIX3-1.2 -40°C to +85°C 3 SC70-3 ABF
LM4041AIM3-1.2 -40°C to +85°C 3 SOT23-3 FZEB
LM4041BIX3-1.2 -40°C to +85°C 3 SC70-3 ABG
LM4041BIM3-1.2 -40°C to +85°C 3 SOT23-3 FZEC
LM4041CIX3-1.2 -40°C to +85°C 3 SC70-3 ABH
LM4041CIM3-1.2 -40°C to +85°C 3 SOT23-3 FZED
LM4041DIX3-1.2 -40°C to +85°C 3 SC70-3 ABI
LM4041DIM3-1.2 -40°C to +85°C 3 SOT23-3 FZEE
*See Selector Guide for a listing of LM4041 Output Voltage,
Initial Accuracy, and Temperature Coefficient specifications.
LM4041
Improved Precision Micropower
Shunt Voltage Reference
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(IR= 100µA, TA= TMIN to TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Note 1: All devices are 100% production tested at +25°C and are guaranteed by design for TA= TMIN to TMAX, as specified.
Note 2: The overtemperature limit for Reverse Breakdown Voltage Tolerance is defined as the room-temperature Reverse
Breakdown Voltage Tolerance ±[(∆VR/ ∆T)(max∆T)(VR)], where ∆VR/ ∆T is the VRtemperature coefficient, max∆T is the
maximum difference in temperature from the reference point of +25°C to TMIN or TMAX, and VRis the reverse breakdown
voltage. The total overtemperature tolerance for the different grades in the temperature range where max∆T = +65°C is
shown below:
A grade: ±0.75% = ±0.1% ±100 ppm/°C ✕65°C
B grade: ±0.85% = ±0.2% ±100 ppm/°C ✕65°C
C grade: ±1.15% = ±0.5% ±100 ppm/°C ✕65°C
D grade: ±1.98% = ±1.0% ±150 ppm/°C ✕65°C
Note 3: Guaranteed by design.
Reverse Current (cathode to anode) ..................................20mA
Forward Current (anode to cathode) ..................................10mA
ESD per Method 3015.7
Human Body Model .......................................................2000V
Machine Model.................................................................200V
Continuous Power Dissipation (TA= +70°C)
3-Pin SC70 (derate 2.17mW/°C above +70°C)............174mW
3-Pin SOT23 (derate 4.01mW/°C above +70°C)..........320mW
Operating Temperature Range ..........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature......................................................+150°C
Lead Temperature (soldering, 10s) ................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Reverse Breakdown Voltage VRTA = +25°C 1.225 V
LM4041A (0.1%) ±1.2 ±9.2
LM4041B (0.2%) ±2.4 ±10.4
LM4041C (0.5%) ±6.0 ±14
Reverse Breakdown Voltage
Tolerance (Note 2) ∆VR
LM4041D (1.0%) ±12 ±24
mV
LM4041A/B/C 45 60
Minimum Operating Current IRMIN LM4041D 45 65 µA
IR = 10mA ±20
LM4041A/B/C ±15 ±100
IR = 1mA LM4041D ±15 ±150
Average Reverse Voltage
Temperature Coefficient
(Note 2)
∆VR/∆T
IR = 100µA±15
ppm/°C
LM4041A/B/C 0.7 1.5
IRMIN ≤ IR ≤ 1mA LM4041D 0.7 2.0
LM4041A/B/C 2.5 8.0
Reverse Breakdown Voltage
Change with Operating
Current Change
∆VR/∆IR
1mA ≤ IR ≤ 12mA LM4041D 2.5 10.0
mV
LM4041A/B/C 0.5 1.5
Reverse Dynamic
Impedance (Note 3) ZRIR = 1mA, f = 120Hz,
IAC = 0.1IRLM4041D 0.5 2.0 Ω
Wideband Noise eNIR = 100µA, 10Hz ≤ f ≤ 10kHz 20 µVRMS
Reverse Breakdown Voltage
Long-Term Stability ∆VRT = 1000h, IR = 100µA 120 ppm
LM4041
Improved Precision Micropower
Shunt Voltage Reference
_______________________________________________________________________________________ 3
-1.0
-0.6
-0.8
-0.2
-0.4
0
0.2
-50 0 50 100
TEMPERATURE DRIFT
LM4041-02
TEMPERATURE (°C)
REFERENCE VOLTAGE CHANGE (mV)
0
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0 5 10 15 20
REVERSE VOLTAGE vs. CURRENT
LM4041-03
REVERSE CURRENT (mA)
REVERSE VOLTAGE CHANGE (mV)
0.5
TA = -40°C
TA = +25°C
TA = +85°C
Typical Operating Characteristics
(IR= 100µA, SC70-3 package, TA= +25°C, unless otherwise noted.)
0
20
60
40
80
100
0 0.80.4 1.2 1.6 2.0
REVERSE CHARACTERISTICS AND
MINIMUM OPERATING CURRENT
LM4041-01
REVERSE VOLTAGE (V)
REVERSE CURRENT (µA)
VGEN
VR
(AC-COUPLED)
2V/div
2mV/div
LOAD-TRANSIENT RESPONSE
LM4041-05
10µs/div
ISHUNT = 1mA ± 250µA,
RL = 10kΩ
SEE FIGURE 1
VGEN
VR
2V/div
2mV/div
LOAD-TRANSIENT RESPONSE
LM4041-06
10µs/div
ISHUNT = 10mA ± 2.5mA,
RL = 1kΩ
SEE FIGURE 1
VGEN
VR
(AC-COUPLED)
2V/div
2mV/div
LOAD-TRANSIENT RESPONSE
LM4041-04
10µs/div
ISHUNT = 100µA ± 25µA,
RL = 100kΩ
SEE FIGURE 1
1k
VB
+
-
ISHUNT
VR
RL
VGEN
Figure 1. Load-Transient Test Circuit
LM4041
Improved Precision Micropower
Shunt Voltage Reference
4 _______________________________________________________________________________________
100 10k1k 100k 1M
OUTPUT IMPEDANCE
vs. FREQUENCY
LM4041-08
FREQUENCY (Hz)
IMPEDANCE (Ω)
1000
0.1
1
10
100
C1 = 0
IR =
C1 = 1µF
IR = 1mA
150µA
10,000
100
10 1k 10k
1000
FREQUENCY (Hz)
NOISE (nV / √Hz)
100
NOISE vs. FREQUENCY
LM4041-09
IR = 200µA
Typical Operating Characteristics (continued)
(IR= 100µA, SC70-3 package, TA= +25°C, unless otherwise noted.)
RS = 30kΩ
SEE FIGURE 2
0841216
STARTUP CHARACTERISTICS
LM4041-07
RESPONSE TIME (µs)
5V
VIN
O
0
1.5V
1.0V
VOUT
O.5V
Pin Description
PIN NAME FUNCTION
1 + Positive Terminal of the Shunt Reference
2−Negative Terminal of the Shunt Reference
3 N.C. Leave this pin unconnected, or connect to pin 2.
RS 30k
VIN
1Hz RATE
VR
Figure 2. Startup Characteristics Test Circuit
LM4041
Improved Precision Micropower
Shunt Voltage Reference
_______________________________________________________________________________________ 5
Detailed Description
The LM4041 shunt references use the bandgap princi-
ple to produce a stable, accurate voltage. The device
behaves similarly to an ideal zener diode; a fixed volt-
age of +1.225V is maintained across its output termi-
nals when biased with 60µA to 12mA of reverse
current. The LM4041 behaves similarly to a silicon
diode when biased with forward currents up 10mA.
Figure 3 shows a typical operating circuit. The LM4041
is ideal for providing a stable reference from a high-
voltage power supply.
Applications Information
The LM4041’s internal pass transistor is used to main-
tain a constant output voltage (VSHUNT) by sinking the
necessary amount of current across a source resistor.
The source resistance (RS) is determined from the load
current (ILOAD) range, supply voltage (VS) variations,
VSHUNT, and desired quiescent current.
Choose the value of RSwhen VSis at a minimum and
ILOAD is at a maximum. Maintain a minimum ISHUNT of
60µA at all times. The RSvalue should be large enough
to keep ISHUNT less than 12mA for proper regulation
when VSis maximum and ILOAD is at a minimum. To
prevent damage to the device, ISHUNT should never
exceed 20mA.
Therefore, the value of RSis bounded by the following
equation:
[VS(MIN) - VR] / [60µA + ILOAD(MAX)] > RS>
[VS(MAX) - VR] / [20mA + ILOAD(MIN)]
Choosing a larger resistance minimizes the total power
dissipation in the circuit by reducing the shunt current
(PD(TOTAL) = VS✕ISHUNT). Provide a safety margin to
incorporate the worst-case tolerance of the resistor
used. Ensure that the resistor’s power rating is ade-
quate, using the following general power equation:
PR= ISHUNT ✕(VS(MAX) - VR)
Output Capacitance
The LM4041 does not require an external capacitor for
frequency stability and is stable for any output capaci-
tance.
Temperature Performance
The LM4041 typically exhibits an output voltage tem-
perature coefficient within ±15ppm/°C. The polarity of
the temperature coefficient may be different from one
device to another; some may have positive coefficients,
and others may have negative coefficients.
Figure 3. Typical Operating Circuit
LM4041
ILOAD
ISHUNT
RS
VS
VR
ISHUNT + ILOAD
Chip Information
TRANSISTOR COUNT: 60
PROCESS: BiCMOS
LM4041
Improved Precision Micropower
Shunt Voltage Reference
6 _______________________________________________________________________________________
SOTPO3L.EPS
Package Information
LM4041
Improved Precision Micropower
Shunt Voltage Reference
_______________________________________________________________________________________ 7
Package Information (continued)
SC70, 3L.EPS
LM4041
Improved Precision Micropower
Shunt Voltage Reference
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
NOTES
