If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range
65C to +150C
Operating Temperature Range
Industrial (LM431xI)
40C to +85C
Commercial (LM431xC)
0C to +70C
Soldering Information
Infrared or Convection (20 sec.)
235C
Wave Soldering (10 sec.)
260C (lead temp.)
Cathode Voltage
37V
Continuous Cathode Current
10 mA to +150
mA
Reference Voltage
0.5V
Reference Input Current
10 mA
Internal Power Dissipation (Notes
3,TO-92 Package
SO-8 Package
SOT-23 Package
0.78W
0.81W
0.28W
micro SMD Package
0.30W
Operating Conditions
Min
Max
Cathode Voltage
V
REF
37V
Cathode Current
1.0 mA
100 mA
LM431
Electrical Characteristics
T
A = 25C unless otherwise specified
Symbol
Parameter
Conditions
Min
Typ
Max
Units
V
REF
Reference Voltage
V
Z =VREF,II = 10 mA
2.440
2.495
2.550
V
V
Z =VREF,II = 10 mA
2.470
2.495
2.520
V
V
Z =VREF,II = 10 mA
2.485
2.500
2.510
V
V
DEV
Deviation of Reference Input Voltage Over
V
Z =VREF,II = 10 mA,
8.0
17
mV
T
Ratio of the Change in Reference Voltage
I
Z =10mA
V
Z from VREF to 10V
1.4
2.7
mV/V
to the Change in Cathode Voltage
Z from 10V to 36V
1.0
2.0
I
REF
Reference Input Current
R
1 =10k
,R
2 = ∞,
2.0
4.0
A
I
∝I
REF
Deviation of Reference Input Current over
R
1 =10k
,R
2 = ∞,
Temperature
I
I = 10 mA,
0.4
1.2
A
T
I
Z(MIN)
Minimum Cathode Current for Regulation
V
0.4
1.0
mA
I
Z(OFF)
Off-State Current
V
0.3
1.0
A
r
Z
V
Z =VREF, LM431A,
0.75
V
Z =VREF, LM431B, LM431C
0.50
Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Electrical specifications do not apply when operating the device
beyond its rated operating conditions.
Note 3: TJ Max = 150C.
Note 4: Ratings apply to ambient temperature at 25C. Above this temperature, derate the TO-92 at 6.2 mW/C, the SO-8 at 6.5 mW/C, the SOT-23 at 2.2 mW/C
and the micro SMD at 3mW/C.
Note 5: Deviation of reference input voltage, VDEV, is defined as the maximum variation of the reference input voltage over the full temperature range.
LM431
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