FEATURES

HIGH LINEARITY: 12 to 14 bits

±0.005% max at 10kHz FS

±0.03% max at 100kHz FS

±0.1% typ at 1MHz FS

V/F OR F/V CONVERSION

6-DECADE DYNAMIC RANGE

GAIN DRIFT: 20ppm/°C max

OUTPUT TTL/CMOS COMPATIBLE

APPLICATIONS

INEXPENSIVE A/D AND D/A CONVERTER

DIGITAL PANEL METERS

TWO-WIRE DIGITAL TRANSMISSION WITH

NOISE IMMUNITY

FM MOD/DEMOD OF TRANSDUCER

SIGNALS

PRECISION LONG TERM INTEGRATOR

HIGH RESOLUTION OPTICAL LINK FOR

ISOLATION

AC LINE FREQUENCY MONITOR

MOTOR SPEED MONITOR AND CONTROL

DESCRIPTION

The VFC320 monolithic voltage-to-frequency and frequency-tovoltage

converter provides a simple low cost method of converting

analog signals into digital pulses. The digital output is an

open collector and the digital pulse train repetition rate is proportional

to the amplitude of the analog input voltage. Output pulses

are compatible with TTL, and CMOS logic families.

High linearity (0.005%, max at 10kHz FS) is achieved with

relatively few external components. Two external resistors and

two external capacitors are required to operate. Full scale frequency

and input voltage are determined by a resistor in series

with –In and two capacitors (one-shot timing and input amplifier

integration). The other resistor is a non-critical open collector

pull-up (fOUT to +VCC). The VFC320 is available in two performance

grades. The VFC320 is specified for the –25°C to +85°C,

range.