8

LTC1448

This circuit shows how to use one LTC1448 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 LTC1448.

The resistor and capacitor on the LTC1448 outputs act as

a lowpass filter for noise.

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

LTC1448

CS/LD

CLK

REF

GND

1448 TA04

0.1

µF

0.1

µF

An Autoranging 8-Channel ADC with Shutdown