ADC0800PD datasheet(5/10 Pages) NSC

5 / 10 page

Application Hints (Continued)

ZERO AND FULL-SCALE ADJUSTMENT

Zero Adjustment

This is the offset voltage required at the

bottom of the R-network (pin 5) to make the 11111111 to

11111110 transition when the input voltage is

LSB (20

mV for a 1024V scale) In most cases this can be accom-

plished by havinga1kX pot on pin 5 A resistor of 475X

can be used as a non-adjustable best approximation from

pin 5 to ground

Full-Scale Adjustment

This is the offset voltage required

at the top of the R-network (pin 15) to make the 00000001

to 00000000 transition when the input voltage is 1

LSB

from full-scale (60 mV less than full-scale for a 1024V

scale) This voltage is guaranteed to be within g2 LSB for

the ADC0800 without adjustment In most cases adjust-

ment can be accomplished by having a 1 kX pot on pin 15

Typical Applications

General Connection

TLH5670 – 11

Hi-Voltage CMOS Output Levels

0V to 10V VIN range

0V to 10V output levels

TLH5670 – 12

Ratiometric Input Signal with Tracking Reference

TLH5670 – 4

ADC0800PD Datasheet(PDF) 5 Page - National Semiconductor (TI)