19-1787; Rev 5; 7/05
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
The LM4040 is a precision two-terminal shunt mode,
bandgap voltage reference available in fixed reverse
breakdown voltages of 2.048V, 2.500V, 3.000V, 3.3V,
4.096V, and 5.000V. Ideal for space-critical applications, the LM4040 is offered in the subminiature 3-pin
SC70 surface-mount package (1.8mm ✕ 1.8mm), 50%
smaller than comparable devices in SOT23 surfacemount 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 LM4040 has a 60µA to 15mA shunt
current capability with low dynamic impedance, ensuring stable reverse breakdown voltage accuracy over a
wide range of operating temperatures and currents.
The LM4040 does not require an external stabilizing
capacitor while ensuring stability with any capacitive
load.
The LM4040 is guaranteed over the temperature range
of -40°C to +125°C.
For a 1.225V output version, refer to the LM4041 data
sheet.
Features
♦ Ultra-Small 3-Pin SC70 Package
♦ 0.1% (max) Initial Accuracy
♦ 100ppm/°C (max) Temperature Coefficient
Guaranteed over -40°C to +125°C Temperature
Range
♦ Wide Operating Current Range: 60µA to 15mA
♦ Low 28µVRMS Output Noise (10Hz to 10kHz)
♦ 2.048V, 2.500V, 3.000V, 3.3V, 4.096V, and 5.000V
Fixed Reverse Breakdown Voltages
♦ No Output Capacitors Required
♦ Tolerates Capacitive Loads
Selector Guide
OUTPUT
PINVOLTAGE
PACKAGE
(V)
PART
TEMP RANGE
LM4040_IM3-2.1
-40°C to +85°C
3 SOT23-3
2.048
Portable, Battery-Powered Equipment
LM4040_IX3-2.1
-40°C to +85°C
3 SC70-3
2.048
Notebook Computers
LM4040_EM3-2.1 -40°C to +125°C 3 SOT23-3
________________________Applications
Cell Phones
Industrial Process Controls
Pin Configuration
TOP VIEW
+ 1
LM4040
3
N.C.*
- 2
SC70-3/SOT23-3
*PIN 3 MUST BE LEFT FLOATING
OR CONNECTED TO PIN 2.
2.048
LM4040_EX3-2.1
-40°C to +125°C 3 SC70-3
2.048
LM4040_IM3-2.5
-40°C to +85°C
3 SOT23-3
2.500
LM4040_IX3-2.5
-40°C to +85°C
3 SC70-3
2.500
LM4040_EM3-2.5 -40°C to +125°C 3 SOT23-3
2.500
LM4040_EX3-2.5
-40°C to +125°C 3 SC70-3
2.500
LM4040_IM3-3.0
-40°C to +85°C
3 SOT23-3
3.000
LM4040_IX3-3.0
-40°C to +85°C
3 SC70-3
3.000
LM4040_EM3-3.0 -40°C to +125°C 3 SOT23-3
3.000
LM4040_EX3-3.0
-40°C to +125°C 3 SC70-3
3.000
LM4040_EX3-3.3
-40°C to +125°C 3 SC70-3
3.300
LM4040_IM3-4.1
-40°C to +85°C
3 SOT23-3
4.096
LM4040_IX3-4.1
-40°C to +85°C
3 SC70-3
4.096
LM4040_EM3-4.1 -40°C to +125°C 3 SOT23-3
4.096
LM4040_EX3-4.1
-40°C to +125°C 3 SC70-3
4.096
LM4040_IM3-5.0
-40°C to +85°C
3 SOT23-3
5.000
LM4040_IX3-5.0
-40°C to +85°C
3 SC70-3
5.000
LM4040_EM3-5.0 -40°C to +125°C 3 SOT23-3
5.000
LM4040_EX3-5.0
5.000
-40°C to +125°C 3 SC70-3
Ordering Information appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
LM4040
General Description
LM4040
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
ABSOLUTE MAXIMUM RATINGS
Reverse Current (cathode to anode) ..................................20mA
Forward Current (anode to cathode) ..................................10mA
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
LM4040_I_ _ _..................................................-40°C to +85°C
LM4040_E_ _ _ ..............................................-40°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature ......................................................+150°C
Lead Temperature (soldering, 10s)..................................+300°C
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.
ELECTRICAL CHARACTERISTICS—2.048V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
Reverse Breakdown Voltage
Tolerance (Note 2)
Minimum Operating Current
SYMBOL
VR
VR
IRMIN
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4040A (0.1%)
2.046
2.048
2.050
LM4040B (0.2%)
2.044
2.048
2.052
LM4040C (0.5%)
2.038
2.048
2.058
LM4040D (1.0%)
2.028
2.048
2.068
LM4040A
±2.0
±15
LM4040B
±4.0
±17
LM4040C
±10
±23
LM4040D
±20
±41
LM4040A/B/C
45
65
LM4040D
45
70
∆VR/∆T
IR = 1mA
LM4040A/B/C
±15
±100
LM4040D
±15
±150
IRMIN ≤ IR ≤ 1mA
Reverse Dynamic
Impedance (Note 3)
Wideband Noise
Reverse Breakdown Voltage
Long-Term Stability
2
1mA ≤ IR ≤ 15mA
ZR
eN
∆VR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
mV
µA
ppm/°C
±15
IR = 100µA
Reverse Breakdown Voltage
Change with Operating
Current Change
V
±20
IR = 10mA
Average Reverse Voltage
Temperature Coefficient
(Notes 2 and 3)
UNITS
LM4040A/B/C
0.3
1.0
LM4040D
0.3
1.2
LM4040A/B/C
2.5
8.0
LM4040D
2.5
10.0
LM4040A/B
0.3
0.8
LM4040C
0.3
0.9
LM4040D
0.3
1.1
mV
Ω
IR = 100µA, 10Hz ≤ f ≤ 10kHz
28
µVRMS
T = 1000h
120
ppm
_______________________________________________________________________________________
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
LM4040
ELECTRICAL CHARACTERISTICS—2.500V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
Reverse Breakdown Voltage
Tolerance (Note 2)
Minimum Operating Current
SYMBOL
VR
VR
IRMIN
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4040A (0.1%)
2.4975
2.5000
2.5025
LM4040B (0.2%)
2.4950
2.5000
2.5050
LM4040C (0.5%)
2.4875
2.5000
2.5125
LM4040D (1.0%)
2.4750
2.5000
2.5250
LM4040A
±2.0
±19
LM4040B
±4.0
±21
LM4040C
±10
±29
LM4040D
±20
±49
LM4040A/B/C
45
65
LM4040D
45
70
∆VR/∆T
IR = 1mA
LM4040A/B/C
±15
±100
LM4040D
±15
±150
IRMIN ≤ IR ≤ 1mA
Reverse Dynamic
Impedance (Note 3)
Wideband Noise
1mA ≤ IR ≤ 15mA
ZR
eN
Reverse Breakdown Voltage
Long-Term Stability
∆VR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
mV
µA
ppm/°C
±15
IR = 100µA
Reverse Breakdown Voltage
Change with Operating
Current Change
V
±20
IR = 10mA
Average Reverse Voltage
Temperature Coefficient
(Notes 2 and 3)
UNITS
LM4040A/B/C
0.3
1.0
LM4040D
0.4
1.2
LM4040A/B/C
2.5
8.0
LM4040D
2.5
10.0
LM4040A/B
0.3
0.8
LM4040C
0.3
0.9
LM4040D
0.3
1.1
mV
Ω
IR = 100µA, 10Hz ≤ f ≤ 10kHz
35
µVRMS
T = 1000h
120
ppm
_______________________________________________________________________________________
3
LM4040
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
ELECTRICAL CHARACTERISTICS—3.000V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
Reverse Breakdown Voltage
Tolerance (Note 2)
Minimum Operating Current
SYMBOL
VR
VR
IRMIN
CONDITIONS
MIN
TYP
MAX
LM4040A (0.1%)
2.997
3.000
3.003
LM4040B (0.2%)
2.994
3.000
3.006
LM4040C (0.5%)
2.985
3.000
3.015
LM4040D (1.0%)
2.970
3.000
3.030
LM4040A
±3.0
±22
LM4040B
±6.0
±26
LM4040C
±15
±34
LM4040D
±30
±59
LM4040A/B/C
45
67
LM4040D
45
70
TA = +25°C
∆VR/∆T
IR = 1mA
LM4040A/B/C
±15
±100
LM4040D
±15
±150
IRMIN ≤ IR ≤ 1mA
Reverse Dynamic
Impedance (Note 3)
Wideband Noise
Reverse Breakdown Voltage
Long-Term Stability
4
1mA ≤ IR ≤ 15mA
ZR
eN
∆VR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
mV
µA
ppm/°C
±15
IR = 100µA
Reverse Breakdown Voltage
Change with Operating
Current Change
V
±20
IR = 10mA
Average Reverse Voltage
Temperature Coefficient
(Notes 2 and 3)
UNITS
LM4040A/B/C
0.3
1.0
LM4040D
0.3
1.2
LM4040A/B/C
2.5
8.0
LM4040D
2.5
10.0
LM4040A/B
0.3
0.8
LM4040C
0.3
0.9
LM4040D
0.3
1.1
mV
Ω
IR = 100µA, 10Hz ≤ f ≤ 10kHz
45
µVRMS
T = 1000h
120
ppm
_______________________________________________________________________________________
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
LM4040
ELECTRICAL CHARACTERISTICS—3.300V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
Reverse Breakdown Voltage
Tolerance (Note 2)
Minimum Operating Current
SYMBOL
VR
VR
IRMIN
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4040A (0.1%)
3.2967
3.3000
3.3033
LM4040B (0.2%)
3.2934
3.3000
3.3066
LM4040C (0.5%)
3.2835
3.3000
3.3165
LM4040D (1.0%)
3.2670
3.3000
3.3330
LM4040A
±3.0
±22
LM4040B
±6.0
±26
LM4040C
±15
±34
LM4040D
±30
±59
LM4040A/B/C
45
67
LM4040D
45
70
∆VR/∆T
IR = 1mA
LM4040A/B/C
±15
±100
LM4040D
±15
±150
IRMIN ≤ IR ≤ 1mA
Reverse Dynamic
Impedance (Note 3)
Wideband Noise
1mA ≤ IR ≤ 15mA
ZR
eN
Reverse Breakdown Voltage
Long-Term Stability
∆VR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
mV
µA
ppm/°C
±15
IR = 100µA
Reverse Breakdown Voltage
Change with Operating
Current Change
V
±20
IR = 10mA
Average Reverse Voltage
Temperature Coefficient
(Notes 2 and 3)
UNITS
LM4040A/B/C
0.3
1.0
LM4040D
0.3
1.2
LM4040A/B/C
2.5
8.0
LM4040D
2.5
10.0
LM4040A/B
0.3
0.8
LM4040C
0.3
0.9
LM4040D
0.3
1.1
mV
Ω
IR = 100µA, 10Hz ≤ f ≤ 10kHz
50
µVRMS
T = 1000h
120
ppm
_______________________________________________________________________________________
5
LM4040
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
ELECTRICAL CHARACTERISTICS—4.096V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
Reverse Breakdown Voltage
Tolerance (Note 2)
Minimum Operating Current
Average Reverse Voltage
Temperature Coefficient
(Notes 2 and 3)
SYMBOL
VR
VR
IRMIN
∆VR/∆T
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4040A (0.1%)
4.092
4.096
4.100
LM4040B (0.2%)
4.088
4.096
4.104
LM4040C (0.5%)
4.076
4.096
4.116
LM4040D (1.0%)
4.055
4.096
4.137
LM4040A
±4.1
±31
LM4040B
±8.2
±35
LM4040C
±20
±47
LM4040D
±41
±81
LM4040A/B/C
50
73
LM4040D
50
78
IR = 10mA
±30
IR = 1mA
LM4040A/B/C
±20
±100
LM4040D
±20
±150
IRMIN ≤ IR ≤ 1mA
mV
µA
ppm/°C
LM4040A/B/C
0.5
LM4040D
0.5
1.2
1.5
LM4040A/B/C
3.0
10.0
LM4040D
3.0
13.0
LM4040A/B/C
0.5
1.0
LM4040D
0.5
1.3
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
64
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
6
1mA ≤ IR ≤ 15mA
V
±15
IR = 100µA
Reverse Breakdown Voltage
Change with Operating
Current Change
UNITS
∆VR
_______________________________________________________________________________________
Ω
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
LM4040
ELECTRICAL CHARACTERISTICS—5.000V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
Reverse Breakdown Voltage
Tolerance (Note 2)
Minimum Operating Current
SYMBOL
VR
VR
IRMIN
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4040A (0.1%)
4.995
5.000
5.005
LM4040B (0.2%)
4.990
5.000
5.010
LM4040C (0.5%)
4.975
5.000
5.025
LM4040D (1.0%)
4.950
5.000
5.050
LM4040A
±5.0
±38
LM4040B
±10
±43
LM4040C
±25
±58
LM4040D
±50
±99
LM4040A/B/C
54
80
LM4040D
54
85
∆VR/∆T
IR = 1mA
LM4040A/B/C
±20
±100
LM4040D
±20
±150
IRMIN ≤ IR ≤ 1mA
1mA ≤ IR ≤ 15mA
mV
µA
ppm/°C
±15
IR = 100µA
Reverse Breakdown Voltage
Change with Operating
Current Change
V
±30
IR = 10mA
Average Reverse Voltage
Temperature Coefficient
(Notes 2 and 3)
UNITS
LM4040A/B/C
0.5
LM4040D
0.5
1.4
1.8
LM4040A/B/C
3.5
12.0
LM4040D
3.5
15.0
LM4040A/B/C
0.5
1.1
LM4040D
0.5
1.5
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
80
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
∆VR
Ω
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 VR temperature coefficient, max∆T is the
maximum difference in temperature from the reference point of +25°C to TMIN or TMAX, and VR is 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% ±100ppm/°C ✕ 65°C
B grade: ±0.85% = ±0.2% ±100ppm/°C ✕ 65°C
C grade: ±1.15% = ±0.5% ±100ppm/°C ✕ 65°C
D grade: ±1.98% = ±1.0% ±150ppm/°C ✕ 65°C
The total over-temperature tolerance for the different grades in the extended temperature range where max ∆T = +100°C is
shown below:
A grade: ±1.1% = ±0.1% ±100ppm/°C ✕ 100°C
B grade: ±1.2% = ±0.2% ±100ppm/°C ✕ 100°C
C grade: ±1.5% = ±0.5% ±100ppm/°C ✕ 100°C
D grade: ±2.5% = ±1.0% ±150ppm/°C ✕ 100°C
Therefore, as an example, the A-grade LM4040-2.5 has an over-temperature reverse breakdown voltage tolerance of ±2.5V
✕ 0.75% = ±19mV.
Note 3: Guaranteed by design.
_______________________________________________________________________________________
7
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
LM4040
Typical Operating Characteristics
(IR = 100µA, SC70-3 package, TA = +25°C, unless otherwise noted.)
REVERSE CHARACTERISTICS AND
MINIMUM OPERATING CURRENT
LM4040_I_3-3.0
3
2
LM4040_I_3-2.5
LM4040_I_3-2.1
0
0
REFERENCE VOLTAGE CHANGE (mV)
-1
-2
-3
-4
-5
0
50
100
-5
-10
-15
-20
-50
-25
0
REVERSE CURRENT (µA)
25
50
75
125
100
-50
-25
0
TEMPERATURE (°C)
LM4040-2.5V
REVERSE VOLTAGE vs. ISHUNT
TA = -40°C
3
TA = +25°C
TA = +85°C
2
1
6
REVERSE VOLTAGE CHANGE (mV)
LM4040-04
TA = +125°C
4
25
TA = -40°C
5
4
TA = +125°C
3
TA = +85°C
2
1
TA = +25°C
0
0
0
5
10
ISHUNT (mA)
8
15
20
0
50
75
TEMPERATURE (°C)
LM4040-5.0V
REVERSE VOLTAGE vs. ISHUNT
5
REVERSE VOLTAGE CHANGE (mV)
0
LM4040 toc05
REVERSE VOLTAGE (V)
4
5
LM4040 toc03
1
5
1
LM4040-5.0V
TEMPERATURE DRIFT
LM4040-02
LM4040_I_3-5.0
REFERENCE VOLTAGE CHANGE (mV)
LM4040_I_3-4.1
LM4040-01
6
LM4040-2.5V
TEMPERATURE DRIFT
5
10
15
20
ISHUNT (mA)
_______________________________________________________________________________________
100
125
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
LM4040-5.0V
LOAD-TRANSIENT RESPONSE
LM4040-2.5V
LOAD-TRANSIENT RESPONSE
LM4040-2.5V
LOAD-TRANSIENT RESPONSE
LM4040-07
LM4040-06
LM4040-08
+25µA
VR AC-COUPLED
VR AC-COUPLED
2mV/div
10mV/div
-250µA
VR AC-COUPLED
-25µA
-25µA
40µs/div
10µs/div
LM4040-5.0V
LOAD-TRANSIENT RESPONSE
10mV/div
10µs/div
ISHUNT = 100µA ± 25µA
RL = 100kΩ, SEE FIGURE 1
CH1: VGEN 2V/div
CH2: VR AC-COUPLED 2mV/div
ISHUNT = 100µA ± 25µA, RL = 100kΩ, SEE FIGURE 1
ISHUNT = 1mA ± 250µA
RL = 10kΩ, SEE FIGURE 1
LM4040-5.0V
LOAD-TRANSIENT RESPONSE
LM4040-2.5V
LOAD-TRANSIENT RESPONSE
LM4040-09
LM4040-11
LM4040-10
+2.5mA
VGEN
+2.5mA
VGEN
VGEN
+250µA
-250µA
-2.5mA
10mV/div
20mV/div
10µs/div
20mV/div
10µs/div
10µs/div
ISHUNT = 1mA ± 250µA
RL = 10kΩ, SEE FIGURE 1
VR AC-COUPLED
-2.5mA
VR AC-COUPLED
VR AC-COUPLED
+250µA
VGEN
VGEN
VGEN
+25µA
ISHUNT = 10mA ± 2.5mA
RL = 1kΩ, SEE FIGURE 1
ISHUNT = 10mA ± 2.5mA
RL = 1kΩ, SEE FIGURE 1
ISHUNT
VB
LM4040
Typical Operating Characteristics (continued)
(IR = 100µA, SC70-3 package, TA = +25°C, unless otherwise noted.)
1kΩ
+
-
RL
VR
VGEN
Figure 1. Load-Transient Test Circuit
_______________________________________________________________________________________
9
Typical Operating Characteristics (continued)
(IR = 100µA, SC70-3 package, TA = +25°C, unless otherwise noted.)
LM4040-2.5V
STARTUP CHARACTERISTICS
LM4040-5.0V
STARTUP CHARACTERISTICS
LM4040-2.5V
OUTPUT IMPEDANCE vs. FREQUENCY
LM4040-13
5V
1000
LM4040-14
LM4040-12
C1 = 1µF
0V
2V
4V
1V
100
IMPEDANCE (Ω)
0V
VOUT
2V
0V
4
8
C1 = 0
1
RS = 30kΩ
SEE FIGURE 2
0
IR = 150µA
10
IR = 1mA
RS = 16kΩ
SEE FIGURE 2
12 16 20 24 28 32 36
0
0.1
10 20 30 40 50 60 70 80 90
0.1k
1k
10k
100k
RESPONSE TIME (µs)
RESPONSE TIME (µs)
FREQUENCY (Hz)
LM4040-5.0V
OUTPUT IMPEDANCE vs. FREQUENCY
LM4040-2.5V
NOISE vs. FREQUENCY
LM4040-5.0V
NOISE vs. FREQUENCY
10
NOISE (nV/√Hz)
IR = 150µA
IR = 1mA
1
10,000
10,000
NOISE (nV/√Hz)
C1 = 0
LM4040-16
LM4040-15
100
1000
1M
LM4040-17
VOUT
VIN
VIN
5V
0V
IMPEDANCE (Ω)
LM4040
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
1000
C1 = 1µF
0.1
100
0.1k
1k
10k
100k
1M
1
FREQUENCY (Hz)
10
100
1k
10k
FREQUENCY (Hz)
100
1
10
100
FREQUENCY (Hz)
RS
VIN
1Hz RATE
50%
DUTY CYCLE
VR
Figure 2. Startup Characteristics Test Circuit
10
______________________________________________________________________________________
1k
10k
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
PIN
NAME
FUNCTION
1
+
Positive Terminal of the Shunt Reference
2
−
Negative Terminal of the Shunt Reference
3
N.C.
No connection. Leave this pin unconnected or connected to pin 2.
Detailed Description
The LM4040 shunt references use the bandgap principle to produce a stable, accurate voltage. The device
behaves similarly to an ideal zener diode; a fixed voltage is maintained across its output terminals when
biased with 60µA to 15mA of reverse current. The
LM4040 behaves similarly to a silicon diode when
biased with forward currents up 10mA.
Figure 3 shows a typical operating circuit. The LM4040
is ideal for providing a stable reference from a highvoltage power supply.
Applications Information
The LM4040’s internal pass transistor is used to maintain 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 RS when VS is at a minimum and ILOAD
is at a maximum. Maintain a minimum ISHUNT of 60µA at all
times. The RS value should be large enough to keep
ISHUNT less than 15mA for proper regulation when VS is
maximum and ILOAD is at a minimum. To prevent damage
to the device, ISHUNT should never exceed 20mA.
Therefore, the value of RS is 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 adequate, using
the following general power equation:
PDR = ISHUNT ✕ (VS(MAX) - VSHUNT)
VS
ISHUNT + ILOAD
RS
ILOAD
VR
ISHUNT
LM4040
Figure 3. Typical Operating Circuit
Temperature Performance
The LM4040 typically exhibits an output voltage temperature 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.
High Temperature Operation
The maximum junction temperature of the LM4040 is
+150°C. The maximum operating temperature for the
LM4040_E_ is +125°C. At a maximum load current of 15mA
and a maximum output voltage of 5V, the part will dissipate
75mW of power. The power dissipation limits of the 3-pin
SC70 call for a derating value of 2.17mW/°C above +70°C
and thus for 75mW of power dissipation, the part will selfheat to 35.56°C above ambient temperature. If the ambient
temperature is +125°C, the part operates at 159.56°C,
thereby exceeding the maximum junction temperature
value of +150°C. For high-temperature operation, care must
be taken to ensure the combination of ambient temperature,
output power dissipation and package thermal resistance
does not conspire to raise the device temperature beyond
that listed in the Absolute Maximum Ratings. Either reduce
the output load current or the ambient temperature to keep
the part within the limits.
Output Capacitance
The LM4040 does not require an external capacitor for frequency stability and is stable for any output capacitance.
Chip Information
TRANSISTOR COUNT: 60
PROCESS: BiCMOS
______________________________________________________________________________________
11
LM4040
Pin Description
LM4040
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
Ordering Information
PART
LM4040AIM3-2.1-T
LM4040AIX3-2.1-T
LM4040BIM3-2.1-T
LM4040BIX3-2.1-T
LM4040CIM3-2.1-T
LM4040CIX3-2.1-T
LM4040DIM3-2.1-T
LM4040DIX3-2.1-T
LM4040AEM3-2.1-T
LM4040AEX3-2.1-T
LM4040BEM3-2.1-T
LM4040BEX3-2.1-T
LM4040CEM3-2.1-T
LM4040CEX3-2.1-T
LM4040DEM3-2.1-T
LM4040DEX3-2.1-T
LM4040AIM3-2.5-T
LM4040AIX3-2.5-T
LM4040BIM3-2.5-T
LM4040BIX3-2.5-T
LM4040CIM3-2.5-T
LM4040CIX3-2.5-T
LM4040DIM3-2.5-T
LM4040DIX3-2.5-T
LM4040AEM3-2.5-T
LM4040AEX3-2.5-T
LM4040BEM3-2.5-T
LM4040BEX3-2.5-T
LM4040CEM3-2.5-T
LM4040CEX3-2.5-T
LM4040DEM3-2.5-T
LM4040DEX3-2.5-T
LM4040AIM3-3.0-T
LM4040AIX3-3.0-T
LM4040BIM3-3.0-T
LM4040BIX3-3.0-T
LM4040CIM3-3.0-T
LM4040CIX3-3.0-T
LM4040DIM3-3.0-T
LM4040DIX3-3.0-T
LM4040AEM3-3.0-T
LM4040AEX3-3.0-T
LM4040BEM3-3.0-T
LM4040BEX3-3.0-T
LM4040CEM3-3.0-T
12
OUTPUT
VOLTAGE (V)
INITIAL
ACCURACY (%)
TEMPCO
(ppm/°C)
TEMP RANGE
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.048
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
2.500
3.000
3.000
3.000
3.000
3.000
3.000
3.000
3.000
3.000
3.000
3.000
3.000
3.000
0.1
0.1
0.2
0.2
0.5
0.5
1.0
1.0
0.1
0.1
0.2
0.2
0.5
0.5
1.0
1.0
0.1
0.1
0.2
0.2
0.5
0.5
1.0
1.0
0.1
0.1
0.2
0.2
0.5
0.5
1.0
1.0
0.1
0.1
0.2
0.2
0.5
0.5
1.0
1.0
0.1
0.1
0.2
0.2
0.5
100
100
100
100
100
100
150
150
100
100
100
100
100
100
150
150
100
100
100
100
100
100
150
150
100
100
100
100
100
100
150
150
100
100
100
100
100
100
150
150
100
100
100
100
100
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
PIN-PACKAGE
TOP
MARK
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
3 SC70-3
3 SOT23-3
FZEF
ABJ
FZEG
ABK
FZEH
ABL
FZEI
ABM
FZNG
ALF
FZNH
ALG
FZNI
ALH
FZNJ
ALI
FZEJ
ABN
FZEK
ABO
FZEL
ABP
FZEM
ABQ
FZNK
ALJ
FZNL
ALK
FZNM
ALL
FZNN
ALM
FZEN
ABR
FZEO
ABS
FZEP
ABT
FZEQ
ABU
FZNO
ALN
FZNP
ALO
FZNQ
______________________________________________________________________________________
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
PART
LM4040CEX3-3.0-T
OUTPUT
VOLTAGE (V)
INITIAL
ACCURACY (%)
TEMPCO
(ppm/°C)
TEMP RANGE
3.000
0.5
100
-40°C to +125°C
PIN-PACKAGE
3 SC70-3
TOP
MARK
ALP
LM4040DEM3-3.0-T
3.000
1.0
150
-40°C to +125°C
3 SOT23-3
FZNR
LM4040DEX3-3.0-T
3.000
1.0
150
-40°C to +125°C
3 SC70-3
ALQ
LM4040AEX3-3.3-T
3.300
0.1
100
-40°C to +125°C
3 SC70-3
ANY
LM4040BEX3-3.3-T
3.300
0.2
100
-40°C to +125°C
3 SC70-3
ANZ
LM4040CEX3-3.3-T
3.300
0.5
100
-40°C to +125°C
3 SC70-3
AOA
LM4040DEX3-3.3-T
3.300
1.0
150
-40°C to +125°C
3 SC70-3
AOB
FZER
LM4040AIM3-4.1-T
4.096
0.1
100
-40°C to +85°C
3 SOT23-3
LM4040AIX3-4.1-T
4.096
0.1
100
-40°C to +85°C
3 SC70-3
ABV
LM4040BIM3-4.1-T
4.096
0.2
100
-40°C to +85°C
3 SOT23-3
FZES
3 SC70-3
LM4040BIX3-4.1-T
4.096
0.2
100
-40°C to +85°C
LM4040CIM3-4.1-T
4.096
0.5
100
-40°C to +85°C
3 SOT23-3
FZET
ABW
LM4040CIX3-4.1-T
4.096
0.5
100
-40°C to +85°C
3 SC70-3
ABX
LM4040DIM3-4.1-T
4.096
1.0
150
-40°C to +85°C
3 SOT23-3
FZEU
LM4040DIX3-4.1-T
4.096
1.0
150
-40°C to +85°C
3 SC70-3
ABY
LM4040AEM3-4.1-T
4.096
0.1
100
-40°C to +125°C
3 SOT23-3
FZNS
LM4040AEX3-4.1-T
4.096
0.1
100
-40°C to +125°C
3 SC70-3
ALR
LM4040BEM3-4.1-T
4.096
0.2
100
-40°C to +125°C
3 SOT23-3
FZNT
LM4040BEX3-4.1-T
4.096
0.2
100
-40°C to +125°C
3 SC70-3
ALS
LM4040CEM3-4.1-T
4.096
0.5
100
-40°C to +125°C
3 SOT23-3
LM4040CEX3-4.1-T
4.096
0.5
100
-40°C to +125°C
3 SC70-3
FZNU
LM4040DEM3-4.1-T
4.096
1.0
150
-40°C to +125°C
3 SOT23-3
LM4040DEX3-4.1-T
4.096
1.0
150
-40°C to +125°C
3 SC70-3
ALU
LM4040AIM3-5.0-T
5.000
0.1
100
-40°C to +85°C
3 SOT23-3
FZEV
LM4040AIX3-5.0-T
5.000
0.1
100
-40°C to +85°C
3 SC70-3
LM4040BIM3-5.0-T
5.000
0.2
100
-40°C to +85°C
3 SOT23-3
FZEW
LM4040BIX3-5.0-T
5.000
0.2
100
-40°C to +85°C
3 SC70-3
ACA
LM4040CIM3-5.0-T
5.000
0.5
100
-40°C to +85°C
3 SOT23-3
FZEX
LM4040CIX3-5.0-T
5.000
0.5
100
-40°C to +85°C
3 SC70-3
ACB
LM4040DIM3-5.0-T
5.000
1.0
150
-40°C to +85°C
3 SOT23-3
FZEY
LM4040DIX3-5.0-T
5.000
1.0
150
-40°C to +85°C
3 SC70-3
LM4040AEM3-5.0-T
5.000
0.1
100
-40°C to +125°C
3 SOT23-3
LM4040AEX3-5.0-T
5.000
0.1
100
-40°C to +125°C
3 SC70-3
ALT
FZNV
ABZ
ACC
FZNW
ALV
LM4040BEM3-5.0-T
5.000
0.2
100
-40°C to +125°C
3 SOT23-3
LM4040BEX3-5.0-T
5.000
0.2
100
-40°C to +125°C
3 SC70-3
FZNX
ALW
LM4040CEM3-5.0-T
5.000
0.5
100
-40°C to +125°C
3 SOT23-3
FZNY
LM4040CEX3-5.0-T
5.000
0.5
100
-40°C to +125°C
3 SC70-3
ALX
______________________________________________________________________________________
13
LM4040
Ordering Information (continued)
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
SOT23 L.EPS
LM4040
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
PACKAGE OUTLINE, 3L SOT-23
21-0051
14
______________________________________________________________________________________
F
1
1
Improved Precision Micropower Shunt Voltage
Reference with Multiple Reverse Breakdown Voltages
SC70, 3L.EPS
PACKAGE OUTLINE, 3L SC70
21-0075
C
1
1
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.
15 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2005 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products, Inc.
LM4040
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
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