User Manual

Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Absolute Maximum Supply Voltage 5.5V
Power Dissipation (Note 2)
ESD Susceptibility (Note 3) 1.5 kV
Sense Current (peak, for 200 msec) (Note 4) 10A
Sink Current for PWM pin 1mA
Voltage on Pin 5 5.25V
Maximum Junction Temperature 150˚C
Storage Temperature −65˚C to +150˚C
Lead Temperature (Soldering, 10 sec) 260˚C
Operating Ratings (Note 1)
Input Voltage 2.0V to 5.25V
Sense Current (continuous) (Note 4) 7A
Junction Temperature Range −40˚C to +125˚C
Electrical Characteristics
LM3812-1.0, LM3813-1.0
V
DD
= 5.0V for the following specifications. Supply bypass capacitor is 1 µF and filter capacitor is 0.1 µF.
Symbol Parameter Conditions
Typ
(Note 5)
Limit
(Note 6)
Units
I
ACC
Average Current Accuracy
(Note 7)
at 0.9A current 0.9
A
0.882 / 0.864 A (min)
0.918 / 0.936 A (max)
e
n
Effective Output Noise (rms) 2 mA
LM3812-7.0, LM3813-7.0
V
DD
= 5.0V for the following specifications. Supply bypass capacitor is 1 µF and filter capacitor is 0.1 µF.
Symbol Parameter Conditions
Typ
(Note 5)
Limit
(Note 6)
Units
I
ACC
Average Current Accuracy
(Note 7)
at 2.5A current (Note 8) 2.5 A
2.400 / 2.350 A (min)
2.600 / 2.650 A (max)
e
n
Effective Output Noise (rms) 20 mA
Common Device Parameters
Unless otherwise specified, V
DD
= 5.0V for the following specifications. Supply bypass capacitor is 1 µF and filter capacitor is
0.1 µF.
Symbol Parameter Conditions
Typ
(Note 5)
Limit
(Note 6)
Units
I
Q1
Quiescent Current Normal Mode, SD = high 100 µA
160 µA (max)
I
Q2
Quiescent Current Shutdown Mode, SD = low 2.5 µA
10 µA (max)
D
RES
PWM Resolution 0.1 %
t
S
Sampling Time 52 ms
40 ms (min)
80 ms (max)
f
P
Frequency of PWM Waveform 20 Hz
12.5 Hz (min)
25 Hz (max)
V
TH
Threshold High Level for SD 1.2 V
1.8 V (min)
V
TL
Threshold Low Level for SD 1.3 V
0.7 V (max)
LM3812/LM3813
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