10

LTC1446/LTC1446L

An Autoranging 8-Channel ADC with Shutdown

LTC1296

50k

74HC04

5V

5V

CS

22

µF

µP

CLK

8 ANALOG

INPUT CHANNELS

CH0

COM

SSO

REF –

CH7

REF+

50k

0.1

µF

100

Ω

100

Ω

LTC1446

CS/LD

CLK

GND

1446/46L F03

0.1

µF

0.1

µF

2N3906

This circuit shows how to use one LTC1446 to make an

autoranging ADC. The microprocessor sets the reference

span and the Common pin for the analog input by loading

controls the Common pin for the analog inputs to the

down pin that goes low in shutdown mode. This will turn

off the PNP transistor supplying power to the LTC1446.

The resistor and capacitor on the LTC1446 outputs act as

a lowpass filter for noise.