Maxim LM4051BEM3-1.2+T 50ppm/â°c precision micropower shunt voltage references with multiple reverse breakdown voltage Datasheet

19-2563; Rev 4; 5/09
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
The LM4050/LM4051 are precision two-terminal, shuntmode, bandgap voltage references available in fixed
reverse breakdown voltages of 1.225V, 2.048V, 2.500V,
3.000V, 3.3V, 4.096V, and 5.000V. Ideal for space-critical applications, the LM4050/LM4051 are offered in the
subminiature 3-pin SC70 surface-mount packages
(1.8mm x 1.8mm), 50% smaller than comparable
devices in SOT23 surface-mount package (SOT23 versions are also available).
Laser-trimmed resistors ensure excellent initial
accuracy. With a 50ppm/°C temperature coefficient,
these devices are offered in three grades of initial accuracy ranging from 0.1% to 0.5%. The LM4050/LM4051
have 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 LM4050/LM4051 do
not require an external stabilizing capacitor while
ensuring stability with any capacitive loads.
The LM4050/LM4051 specifications are guaranteed
over the temperature range of -40°C to +125°C.
________________________Applications
Features
♦ 50ppm/°C (max) Temperature Coefficient
Guaranteed over the -40°C to +125°C
Temperature Range
♦ Ultra-Small 3-Pin SC70 Package
♦ 0.1% (max) Initial Accuracy
♦ Wide Operating Current Range: 60µA to 15mA
♦ Low 28µVRMS Output Noise (10Hz to 10kHz)
♦ 1.225V, 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
PART
TEMP RANGE
OUTPUT
PINVOLTAGE
PACKAGE
(V)
LM4050_EM3-2.1+T -40°C to +125°C 3 SOT23-3
2.048
LM4050_EX3-2.1+T -40°C to +125°C 3 SC70-3
2.048
LM4050_EM3-2.5+T -40°C to +125°C 3 SOT23-3
2.500
LM4050_EX3-2.5+T -40°C to +125°C 3 SC70-3
2.500
Portable, Battery-Powered Equipment
LM4050_EM3-3.0+T -40°C to +125°C 3 SOT23-3
3.000
Notebook Computers
LM4050_EX3-3.0+T -40°C to +125°C 3 SC70-3
3.000
Cell Phones
Industrial Process Controls
Typical Operating Circuit
VS
LM4050_EX3-3.3+T -40°C to +125°C 3 SC70-3
3.300
LM4050_EM3-4.1+T -40°C to +125°C 3 SOT23-3
4.096
LM4050_EX3-4.1+T -40°C to +125°C 3 SC70-3
4.096
LM4050_EM3-5.0+T -40°C to +125°C 3 SOT23-3
5.000
LM4050_EX3-5.0+T -40°C to +125°C 3 SC70-3
5.000
LM4051_EM3-1.2+T -40°C to +125°C 3 SOT23-3
1.225
LM4051_EX3-1.2+T -40°C to +125°C 3 SC70-3
1.225
+Denotes a lead(pb)-free/RoHS-compliant package.
T = Tape and reel.
Ordering Information appears at end of data sheet.
Pin Configuration
ISHUNT + ILOAD
RS
TOP VIEW
ILOAD
VR
+
1
ISHUNT
LM4050/
LM4051
LM4050
3
N.C.*
- 2
SC70/SOT23
*PIN 3 MUST BE LEFT FLOATING
OR CONNECTED TO PIN 2.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
LM4050/LM4051
General Description
LM4050/LM4051
50ppm/°C Precision Micropower Shunt Voltage
References 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
LM4050/LM4051_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—1.225V
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
SYMBOL
VR
Reverse Breakdown Voltage
Tolerance (Note 2)
VRTOL
Minimum Operating Current
IRMIN
Average Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
TA = +25°C
MIN
TYP
MAX
LM4051A (0.1%)
1.2238
1.2250
1.2262
LM4051B (0.2%)
1.2226
1.2250
1.2275
LM4051C (0.5%)
1.2189
UNITS
V
1.2250
1.2311
LM4051A
±1.2
±7
LM4051B
±2.4
±9
LM4051C
±6.0
±12
45
60
µA
IR = 10mA
IR = 1mA
±20
±15
±50
ppm/°C
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.7
1.5
1mA ≤ IR ≤ 12mA
2.5
8.0
1.5
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz, IAC = 0.1IR
0.5
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
20
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
2
CONDITIONS
ΔVR
_______________________________________________________________________________________
Ω
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
(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, 3)
SYMBOL
VR
VRTOL
CONDITIONS
MIN
TYP
MAX
LM4050A (0.1%)
2.0460
2.0480
2.0500
LM4050B (0.2%)
2.0439
2.0480
2.0521
LM4050C (0.5%)
2.0378
2.0480
2.0582
LM4050A
±2.0
±12
LM4050B
±4.0
±14
LM4050C
±10
±20
45
65
µA
IR = 10mA
IR = 1mA
±20
±15
±50
ppm/°C
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.3
1.0
1mA ≤ IR ≤ 15mA
2.5
8.0
LM4050A/B
0.3
0.8
LM4050C
0.3
0.9
TA = +25°C
IRMIN
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
UNITS
V
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
28
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
ΔVR
Ω
_______________________________________________________________________________________
3
LM4050/LM4051
ELECTRICAL CHARACTERISTICS—2.048V
LM4050/LM4051
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
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
Average Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
SYMBOL
VR
VRTOL
MIN
TYP
MAX
LM4050A (0.1%)
2.4975
2.5000
2.5025
LM4050B (0.2%)
2.4950
2.5000
2.5050
LM4050C (0.5%)
2.4875
2.5000
2.5125
LM4050A
±2.5
±15
LM4050B
±5.0
±18
LM4050C
±13
±25
45
65
µA
±50
ppm/°C
TA = +25°C
IRMIN
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
IR = 10mA
±20
IR = 1mA
±15
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.3
1.0
1mA ≤ IR ≤ 15mA
2.5
8.0
LM4050A/B
0.3
0.8
LM4050C
0.3
0.9
UNITS
V
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
35
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
4
CONDITIONS
ΔVR
_______________________________________________________________________________________
Ω
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
(IR = 100µA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Reverse Breakdown Voltage
SYMBOL
VR
Reverse Breakdown Voltage
Tolerance (Note 2)
VRTOL
Minimum Operating Current
IRMIN
Average Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4050A (0.1%)
2.9970
3.0000
3.0030
LM4050B (0.2%)
2.9940
3.0000
3.0060
LM4050C (0.5%)
2.9850
UNITS
V
3.0000
3.0150
LM4050A
±3.0
±18
LM4050B
±6.0
±21
LM4050C
±15
±30
45
67
µA
±50
ppm/°C
IR = 10mA
±20
IR = 1mA
±15
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.3
1.0
1mA ≤ IR ≤ 15mA
2.5
8.0
LM4050A/B
0.3
0.8
LM4050C
0.3
0.9
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
45
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
ΔVR
Ω
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
SYMBOL
VR
Reverse Breakdown Voltage
Tolerance (Note 2)
VRTOL
Minimum Operating Current
IRMIN
Average Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
CONDITIONS
TA = +25°C
MIN
TYP
MAX
LM4050A (0.1%)
3.2967
3.3000
3.3033
LM4050B (0.2%)
3.2934
3.3000
3.3066
LM4050C (0.5%)
3.2835
UNITS
V
3.3000
3.3165
LM4050A
±3.0
±18
LM4050B
±6.0
±21
LM4050C
±15
±30
45
67
µA
±50
ppm/°C
IR = 10mA
±20
IR = 1mA
±15
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.3
1.0
1mA ≤ IR ≤ 15mA
2.5
8.0
LM4050A/B
0.3
0.8
LM4050C
0.3
0.9
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz,
IAC = 0.1IR
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
50
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
ΔVR
Ω
_______________________________________________________________________________________
5
LM4050/LM4051
ELECTRICAL CHARACTERISTICS—3.000V
LM4050/LM4051
50ppm/°C Precision Micropower Shunt Voltage
References 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
SYMBOL
VR
Reverse Breakdown Voltage
Tolerance (Note 2)
VRTOL
Minimum Operating Current
IRMIN
Average Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
MIN
TYP
MAX
LM4050A (0.1%)
4.0919
4.0960
4.1001
LM4050B (0.2%)
4.0878
4.0960
4.1042
LM4050C (0.5%)
4.0755
4.0960
4.1165
LM4050A
±4.1
±25
LM4050B
±8.2
±29
LM4050C
±20
±41
50
73
µA
±50
ppm/°C
TA = +25°C
IR = 10mA
±30
IR = 1mA
±20
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.5
1.2
1mA ≤ IR ≤ 15mA
3.0
10.0
1.0
UNITS
V
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz, IAC = 0.1IR
0.5
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
64
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
6
CONDITIONS
ΔVR
_______________________________________________________________________________________
Ω
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
(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, 3)
SYMBOL
VR
VRTOL
CONDITIONS
MIN
TYP
MAX
LM4050A (0.1%)
4.9950
5.0000
5.0050
LM4050B (0.2%)
4.9900
5.0000
5.0100
LM4050C (0.5%)
4.9750
5.0000
5.0250
LM4050A
±5.0
±30
LM4050B
±10
±35
LM4050C
±25
±50
54
80
µA
IR = 10mA
±30
IR = 1mA
±20
±50
ppm/°C
IR = 100µA
±15
IRMIN ≤ IR ≤ 1mA
0.5
1.4
1mA ≤ IR ≤ 15mA
3.5
12.0
1.1
TA = +25°C
IRMIN
ΔVR/ΔT
Reverse Breakdown Voltage
Change with Operating
Current Change
UNITS
V
mV
mV
Reverse Dynamic
Impedance (Note 3)
ZR
IR = 1mA, f = 120Hz, IAC = 0.1IR
0.5
Wideband Noise
eN
IR = 100µA, 10Hz ≤ f ≤ 10kHz
80
µVRMS
T = 1000h
120
ppm
Reverse Breakdown Voltage
Long-Term Stability
ΔVR
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 limit over the full temperature range for the reverse breakdown voltage tolerance is defined as:
[VRTOL] ±[(ΔVR / ΔT) X (maxΔT) X (VR)]
where ΔVR / ΔT is the VR temperature coefficient, maxΔT is the difference from the +25°C reference point to TMIN or TMAX,
and VR is the reverse breakdown voltage.
The total tolerance over the full temperature range for the different grades where maxΔT = +100°C is shown below:
• A grade: ±0.6% = ±0.1% ±50ppm/°C ✕ 100°C
• B grade: ±0.7% = ±0.2% ±50ppm/°C ✕ 100°C
• C grade: ±1.0% = ±0.5% ±50ppm/°C ✕ 100°C
Note 3: Guaranteed by design.
_______________________________________________________________________________________
7
LM4050/LM4051
ELECTRICAL CHARACTERISTICS—5.000V
Typical Operating Characteristics
(IR = 100µA, SC70-3 package, TA = +25°C, unless otherwise noted.)
REVERSE CHARACTERISTICS AND
MINIMUM OPERATING CURRENT
4
LM4050_I_3-3.0
3
2
5.001
2.496
2.494
2.492
LM4050_I_3-2.5
4.995
4.993
4.989
0
2.490
50
100
4.987
-40
-15
REVERSE CURRENT (μA)
10
35
60
85
110
135
-40
-15
10
TEMPERATURE (°C)
TA = -40°C
TA = +25°C
TA = +85°C
2
1
6
REVERSE VOLTAGE CHANGE (mV)
LM4050 toc04
TA = +125°C
3
60
LM4050-5.0V
REVERSE VOLTAGE vs. ISHUNT
5
4
35
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
85
TEMPERATURE (°C)
LM4050-2.5V
REVERSE VOLTAGE vs. ISHUNT
REVERSE VOLTAGE CHANGE (mV)
4.997
4.991
LM4050_I_3-2.1
0
4.999
LM4050 toc05
1
5.003
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
5
MAX4050 toc03
2.498
OUTPUT VOLTAGE vs. TEMPERATURE
(VOUT = 5.000V)
MAX4050 toc02
LM4050_I_3-5.0
LM4050_I_3-4.1
OUTPUT VOLTAGE vs. TEMPERATURE
(VOUT = 2.500V)
LM4050 toc01
6
REVERSE VOLTAGE (V)
LM4050/LM4051
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
0
5
10
15
ISHUNT (mA)
_______________________________________________________________________________________
20
110
135
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
LM4050-2.5V
LOAD-TRANSIENT RESPONSE
LM4050-2.5V
LOAD-TRANSIENT RESPONSE
LM4050-5.0V
LOAD-TRANSIENT RESPONSE
LM4050 toc06
LM4050 toc08
LM4050 toc07
VGEN
ISHUNT = 1mA ± 250μA
RL = 10kΩ, SEE FIGURE 1.
ISHUNT = 100μA ± 25μA
RL = 100kΩ, SEE FIGURE 1.
LM4050-2.5V
LOAD-TRANSIENT RESPONSE
LM4050-5.0V
LOAD-TRANSIENT RESPONSE
10mV/div
10μs/div
40μs/div
CH1: VGEN 2V/div
CH2: VR AC-COUPLED 2mV/div
ISHUNT = 100μA ± 25μA, RL = 100kΩ, SEE FIGURE 1.
LM4050-5.0V
LOAD-TRANSIENT RESPONSE
LM4050 toc10
LM4050 toc09
LM4050 toc11
+2.5mA
VGEN
-2.5mA
VR AC-COUPLED
-250μA
10mV/div
+2.5mA
20mV/div
10μs/div
10μs/div
-2.5mA
VR AC-COUPLED
VGEN
VGEN
+250μA
VR AC-COUPLED
VR AC-COUPLED
10mV/div
10μs/div
ISHUNT = 1mA ± 250μA
RL = 10kΩ, SEE FIGURE 1.
-250μA
-25μA
VR AC-COUPLED
VR AC-COUPLED
-25μA
2mV/div
+250μA
+25μA
VGEN
VGEN
+25μA
20mV/div
10μs/div
ISHUNT = 10mA ± 2.5mA
RL = 1kΩ, SEE FIGURE 1.
ISHUNT = 10mA ± 2.5mA
RL = 1kΩ, SEE FIGURE 1.
ISHUNT
VB
1kΩ
+
-
RL
VR
VGEN
Figure 1. Load-Transient Test Circuit
_______________________________________________________________________________________
9
LM4050/LM4051
Typical Operating Characteristics (continued)
(IR = 100µA, SC70-3 package, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(IR = 100µA, SC70-3 package, TA = +25°C, unless otherwise noted.)
LM4050-5.0V
STARTUP CHARACTERISTICS
LM4050 toc12
LM4050 toc13
5V
1000
5V
VIN
VIN
C1 = 1μF
0
2V
4V
1V
0
100
IMPEDANCE (Ω)
0
VOUT
VOUT
LM4050-2.5V
OUTPUT IMPEDANCE vs. FREQUENCY
LM4050 toc14
LM4050-2.5V
STARTUP CHARACTERISTICS
2V
0
IR = 150μA
10
C1 = 0
1
IR = 1mA
RS = 30kΩ
RS = 16kΩ
4
8
12 16 20 24 28 32 36
0
RESPONSE TIME (μs)
SEE FIGURE 2.
1k
10k
100k
FREQUENCY (Hz)
LM4050-2.5V
NOISE vs. FREQUENCY
LM4050-5.0V
NOISE vs. FREQUENCY
NOISE (nV/√Hz)
IR = 150μA
10,000
IR = 1mA
10,000
NOISE (nV/√Hz)
C1 = 0
LM4050 toc16
LM4050 toc15
100
1
0.1k
RESPONSE TIME (μs)
1M
SEE FIGURE 2.
LM4050-5.0V
OUTPUT IMPEDANCE vs. FREQUENCY
10
0.1
10 20 30 40 50 60 70 80 90
1000
LM4050 toc17
0
IMPEDANCE (Ω)
LM4050/LM4051
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
1000
C1 = 1μF
0.1
100
0.1k
1k
10k
100k
1M
100
1
FREQUENCY (Hz)
10
100
1k
10k
FREQUENCY (Hz)
1
10
100
FREQUENCY (Hz)
RS
VIN
1Hz RATE
50%
DUTY CYCLE
VR
Figure 2. Startup Characteristics Test Circuit
10
______________________________________________________________________________________
1k
10k
50ppm/°C Precision Micropower Shunt Voltage
References 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 LM4050/LM4051 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 LM4050/LM4051 clamps to a voltage of
one diode drop below ground when biased with forward currents up 10mA.
Figure 3 shows a typical operating circuit. The
LM4050/LM4051 are ideal for providing stable references from a high-voltage power supply.
VS
ISHUNT + ILOAD
RS
ILOAD
VR
ISHUNT
LM4050
Figure 3. Typical Operating Circuit
Applications Information
The LM4050/LM4051s’ internal pass transistors are 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)
Temperature Performance
The LM4050/LM4051 typically exhibit output voltage
temperature coefficients within ±15ppm/°C. The polarity of the temperature coefficients 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 LM4050/
LM4051 is +150°C. The maximum operating temperature
for the LM4050/LM4051_E_ is +125°C. At a maximum
load current of 15mA and a maximum output voltage of
5V, the parts 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 parts self-heat to 35.56°C above ambient
temperature. If the ambient temperature is +125°C, the
parts operate at 159.56°C, thereby exceeding the maximum junction temperature value of +150°C. For hightemperature 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 LM4050/LM4051 do not require external capacitors
for frequency stability and are stable for any output
capacitance.
Chip Information
TRANSISTOR COUNT: 60
PROCESS: BiCMOS
______________________________________________________________________________________
11
LM4050/LM4051
Pin Description
LM4050/LM4051
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
Ordering Information
OUTPUT
VOLTAGE
(V)
INITIAL
ACCURACY
(%)
TEMPCO
(ppm/°C)
TEMP RANGE
LM4050AEM3-2.1+T
2.048
0.1
50
-40°C to +125°C
3 SOT23
LM4050AEX3-2.1+T
2.048
0.1
50
-40°C to +125°C
3 SC70
ASM
LM4050BEM3-2.1+T
2.048
0.2
50
-40°C to +125°C
3 SOT23
FZTS
LM4050BEX3-2.1+T
2.048
0.2
50
-40°C to +125°C
3 SC70
ASN
LM4050CEM3-2.1+T
2.048
0.5
50
-40°C to +125°C
3 SOT23
FZTT
LM4050CEX3-2.1+T
2.048
0.5
50
-40°C to +125°C
3 SC70
ASO
LM4050AEM3-2.5+T
2.500
0.1
50
-40°C to +125°C
3 SOT23
FZTU
LM4050AEX3-2.5+T
2.500
0.1
50
-40°C to +125°C
3 SC70
ASP
LM4050BEM3-2.5+T
2.500
0.2
50
-40°C to +125°C
3 SOT23
FZTV
LM4050BEX3-2.5+T
2.500
0.2
50
-40°C to +125°C
3 SC70
ASQ
LM4050CEM3-2.5+T
2.500
0.5
50
-40°C to +125°C
3 SOT23
FZTW
LM4050CEX3-2.5+T
2.500
0.5
50
-40°C to +125°C
3 SC70
ASR
LM4050AEM3-3.0+T
3.000
0.1
50
-40°C to +125°C
3 SOT23
FZTX
LM4050AEX3-3.0+T
3.000
0.1
50
-40°C to +125°C
3 SC70
ASS
LM4050BEM3-3.0+T
3.000
0.2
50
-40°C to +125°C
3 SOT23
FZTY
LM4050BEX3-3.0+T
3.000
0.2
50
-40°C to +125°C
3 SC70
AST
LM4050CEM3-3.0+T
3.000
0.5
50
-40°C to +125°C
3 SOT23
FZTZ
LM4050CEX3-3.0+T
3.000
0.5
50
-40°C to +125°C
3 SC70
ASU
LM4050AEX3-3.3+T
3.300
0.1
50
-40°C to +125°C
3 SC70
AOJ
LM4050BEX3-3.3+T
3.300
0.2
50
-40°C to +125°C
3 SC70
AOK
LM4050CEX3-3.3+T
3.300
0.5
50
-40°C to +125°C
3 SC70
AOL
LM4050AEM3-4.1+T
4.096
0.1
50
-40°C to +125°C
3 SOT23
FZUA
LM4050AEX3-4.1+T
4.096
0.1
50
-40°C to +125°C
3 SC70
LM4050BEM3-4.1+T
4.096
0.2
50
-40°C to +125°C
3 SOT23
LM4050BEX3-4.1+T
4.096
0.2
50
-40°C to +125°C
3 SC70
ASW
LM4050CEM3-4.1+T
4.096
0.5
50
-40°C to +125°C
3 SOT23
FZUC
LM4050CEX3-4.1+T
4.096
0.5
50
-40°C to +125°C
3 SC70
LM4050AEM3-5.0+T
5.000
0.1
50
-40°C to +125°C
3 SOT23
LM4050AEX3-5.0+T
5.000
0.1
50
-40°C to +125°C
3 SC70
LM4050BEM3-5.0+T
5.000
0.2
50
-40°C to +125°C
3 SOT23
LM4050BEX3-5.0+T
5.000
0.2
50
-40°C to +125°C
3 SC70
ASZ
LM4050CEM3-5.0+T
5.000
0.5
50
-40°C to +125°C
3 SOT23
FZUF
PART
PIN-PACKAGE
TOP
MARK
FZTR
ASV
FZUB
ASX
FZUD
ASY
FZUE
LM4050CEX3-5.0+T
5.000
0.5
50
-40°C to +125°C
3 SC70
LM4051AEM3-1.2+T
1.225
0.1
50
-40°C to +125°C
3 SOT23
LM4051AEX3-1.2+T
1.225
0.1
50
-40°C to +125°C
3 SC70
ASJ
LM4051BEM3-1.2+T
1.225
0.2
50
-40°C to +125°C
3 SOT23
FZTP
LM4051BEX3-1.2+T
1.225
0.2
50
-40°C to +125°C
3 SC70
ASK
LM4051CEM3-1.2+T
1.225
0.5
50
-40°C to +125°C
3 SOT23
FZTQ
LM4051CEX3-1.2+T
1.225
0.5
50
-40°C to +125°C
3 SC70
12
______________________________________________________________________________________
ATA
FZTO
ASL
50ppm/°C Precision Micropower Shunt Voltage
References with Multiple Reverse Breakdown Voltages
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
3 SOT23
U3+1
21-0051
3 SC70
X3+2
21-0075
Revision History
REVISION
NUMBER
REVISION
DATE
0
7/02
Initial release
4
5/09
Added lead-free notation and corrected topmarks in the
Ordering Information and Selector Guide sections
DESCRIPTION
PAGES CHANGED
—
1, 12
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.
13 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
LM4050/LM4051
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
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