LM431
Absolute Maximum Ratings
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range
Operating Temperature Range
Industrial (LM431xI)
Commercial (LM431xC)
Soldering Information
Infrared or Convection (20 sec.)
Wave Soldering (10 sec.)
Cathode Voltage
Continuous Cathode Current
235˚C
260˚C (lead temp.)
37V
−10 mA to +150
mA
−40˚C to +85˚C
0˚C to +70˚C
−65˚C to +150˚C
Reference Voltage
Reference Input Current
Internal Power Dissipation (Notes 3,
TO-92 Package
SO-8 Package
SOT-23 Package
micro SMD Package
Operating Conditions
Min
Cathode Voltage
Cathode Current
V
REF
1.0 mA
−0.5V
10 mA
0.78W
0.81W
0.28W
0.30W
Max
37V
100 mA
LM431
Electrical Characteristics
T
A
= 25˚C unless otherwise specified
Symbol
V
REF
Parameter
Reference Voltage
Conditions
V
Z
= V
REF
, I
I
= 10 mA
LM431A
)
V
Z
= V
REF
, I
I
= 10 mA
LM431B
)
V
Z
= V
REF
, I
I
= 10 mA
LM431C
)
V
DEV
Deviation of Reference Input Voltage Over
Temperature (Note 5)
Ratio of the Change in Reference Voltage
to the Change in Cathode Voltage
I
REF
∝
I
REF
Reference Input Current
Deviation of Reference Input Current over
Temperature
I
Z(MIN)
I
Z(OFF)
r
Z
Minimum Cathode Current for Regulation
Off-State Current
Dynamic Output Impedance (Note 6)
V
Z
= V
REF
, I
I
= 10 mA,
T
A
= Full Range
)
I
Z
= 10 mA
)
V
Z
from V
REF
to 10V
V
Z
from 10V to 36V
−1.4
−1.0
2.0
−2.7
−2.0
4.0
µA
mV/V
8.0
17
mV
2.485
2.500
2.510
V
2.470
2.495
2.520
V
Min
2.440
Typ
2.495
Max
2.550
Units
V
R
1
= 10 kΩ, R
2
=
∞
,
I
I
= 10 mA
)
R
1
= 10 kΩ, R
2
=
∞
,
I
I
= 10 mA,
T
A
= Full Range
)
V
Z
= V
REF
)
V
Z
= 36V, V
REF
= 0V
(Figure *NO
TARGET FOR fi*
)
V
Z
= V
REF
, LM431A,
Frequency = 0 Hz
)
V
Z
= V
REF
, LM431B, LM431C
Frequency = 0 Hz
)
0.4
0.4
0.3
1.2
1.0
1.0
0.75
0.50
µA
mA
µA
Ω
Ω
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:
T
J Max
= 150˚C.
Note 4:
Ratings apply to ambient temperature at 25˚C. 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, V
DEV
, is defined as the maximum variation of the reference input voltage over the full temperature range.
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