LM3814 Datasheet, PDF (2/14 Pages) National Semiconductor (TI) – Fast Current Gauge IC with Ultra Low Loss Sense Element and PWM Output

Ordering Information
Order No.^#
Sense Sampling Sensing
NS
Package
Supplied As:
Range Interval*
Method
Package
Number^‡
Type
LM3814M-1.0
±1A
6 ms
High-side
M08A
SO-8
95 units in Rails
LM3814MX-1.0
±1A
6 ms
High-side
M08A
SO-8
2.5k units on Tape and Reel
LM3814M-7.0
±7A
6 ms
High-side
M08A
SO-8
95 units in Rails
LM3814MX-7.0
±7A
6 ms
High-side
M08A
SO-8
2.5k units on Tape and Reel
LM3815M-1.0
±1A
6 ms
Low-side
M08A
SO-8
95 units in Rails
LM3815MX-1.0
±1A
6 ms
Low-side
M08A
SO-8
2.5k units on Tape and Reel
LM3815M-7.0
±7A
6 ms
Low-side
M08A
SO-8
95 units in Rails
LM3815MX-7.0
±7A
6 ms
Low-side
M08A
SO-8
2.5k units on Tape and Reel
# _{Suffix M indicates that the part is available in Surface Mount package. Suffix X indicates that the part is available in 2.5k units}
on Tape and Reel.
* Current is sampled over a fixed interval. The average current during this interval is indicated by the duty cycle of the PWM output
during next interval.
‡ _{The Package code M08A is internal to National Semiconductor and indicates an 8-lead surface mount package, SO-8.}
Pin Description (High-Side, LM3814)
Pin
Name
1
SENSE+, V_DD
2
SENSE−
3
FLTR+
4
FLTR−
5
SD
6
PWM
7
GND
8
GND
Function
High side of internal current sense, also supply voltage.
Low side of internal current sense.
Filter input — provides anti-aliasing for delta sigma modulator.
Filter input.
Shutdown pin. Connected to V_DD through a pull up resistor for normal operation.
When low, the IC goes into a low current mode (typically 3 µA).
PWM output indicates the current magnitude and direction.
Ground
Ground
Pin Description (Low-Side, LM3815)
Pin
Name
1
SENSE+, GND
2
SENSE−
3
FLTR+
4
FLTR−
5
SD
6
PWM
7
GND
8
V_DD
Function
High side of internal current sense, also ground.
Low side of internal current sense.
Filter input – provides anti-aliasing for delta sigma modulator.
Filter input.
Shutdown pin. Connected to V_DD through a pull up resistor for normal operation.
When low, the IC goes into a low current mode (typically 3 µA).
PWM output indicates the current magnitude and direction.
Ground
V_DD (supply)
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