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.