INA138, INA168

8

SBOS122C

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FIGURE 6. Bipolar Current Measurement Using Differential Input of A/D Converter.

FIGURE 7. Multiplexed Measurement Using Logic Signal for Power.

INA168

INA168

Other INA168s

––

––

IN4148

REF

V+

V+

R

L

Serial

I/O

ADS7870

Clock

Divider

Oscillator

BUF

OUT

BUF

IN

REF

OUT

12-Bit

A/D

Converter

BUF

MUX

Digital

I/O

PGIA

+5V

Digital I/O on the ADS7870 provides power to select

the desired INA168. Diodes prevent output current of

the

REF

Serial

I/O

ADS7870

Clock

Divider

Oscillator

BUF

OUT

BUF

IN

REF

OUT

12-Bit

A/D

Converter

BUF

MUX

Digital

I/O

PGIA

+5V

1

2

+5V

5

4

3

1

2

+5V

5

4

3

R

S

RL

25k

Ω

RL

25k

Ω

V+

INA138

INA138

A/D converter programmed for differential input.

Depending on polarity of current, one INA138 provides

an output voltage, the output of the other is zero.