VFC320
VFC
320
SBVS017A – AUGUST 2001
Voltage-to-Frequency
and Frequency-to-Voltage
CONVERTER
FEATURES
DESCRIPTION
q HIGH LINEARITY: 12 to 14 bits
±0.005% max at 10kHz FS
±0.03% max at 100kHz FS
±0.1% typ at 1MHz FS
q V/F OR F/V CONVERSION
q 6-DECADE DYNAMIC RANGE
q GAIN DRIFT: 20ppm/°C max
q OUTPUT TTL/CMOS COMPATIBLE
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.
APPLICATIONS
q INEXPENSIVE A/D AND D/A CONVERTER
q DIGITAL PANEL METERS
q TWO-WIRE DIGITAL TRANSMISSION WITH
NOISE IMMUNITY
q FM MOD/DEMOD OF TRANSDUCER
SIGNALS
q PRECISION LONG TERM INTEGRATOR
q HIGH RESOLUTION OPTICAL LINK FOR
ISOLATION
q AC LINE FREQUENCY MONITOR
q MOTOR SPEED MONITOR AND CONTROL
+VCC
VOUT
fIN
–In
+In
Comparators
–7.5V Ref
Flipflop
fOUT
One-shot
–VCC
C1
Common
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright © 1982, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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