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RC4 1 5 2
Vo lt a g e -t o -Fre q u e n c y Co n ve rt e rs
• Signal isolation:
Features
• Single supply operation
• Pulse output DTL/TTL/CMOS compatible
• Programmable scale factor (K)
• High noise rejection
• Inherent monotonicity
• Easily transmittable output
• Simple full scale trim
– VFC—opto-isolaton—FVC
– ADC with opto-isolation
• Signal encoding:
– FSK modulation/demodulation
– Pulse-width modulation
• Frequency scaling
• DC motor speed control
• Single-ended input, referenced to ground
• V-F or F-V conversion
Description
• Voltage or current input
• Wide dynamic range
The RC4152 is a monolithic circuit containing all of the
active components needed to build a complete voltage-to-
frequency converter. Circuits that convert a DC voltage to a
pulse train can be built by adding a few resistors and capaci-
tors to the internal comparator, one-shot, voltage reference,
and switched current source. Frequency-to-voltage convert-
ers (FVCs) and many other signal conditioning circuits are
also easily created using these converters.
Applications
• Precision voltage-to-frequency converters
• Pulse-width modulators
• Programmable pulse generators
• Frequency-to-voltage converters
• Integrating analog-to-digital converters
• Long-term analog integrators
• Signal conversion:
The RC4151 was the first monolithic VFC available and
offers guaranteed temperature and accuracy specifications.
The converter is available in a standard 8-pin plastic DIP.
– Current-to-Frequency
– Temperature-to-Frequency
– Pressure-to-Frequency
– Capacitance-to-Frequency
– Frequency-to-Current
Functional Block Diagram
4152
Switched
Current
Source
Switched
Current
Source Output
Voltage
Reference
1
-VS
8
Open Loop
Comparator
Switched
Reference
Output
Switched
Voltage
Reference
2
3
4
7
6
5
Comparator
Inputs
Open Collector
Output
Precision
One Shot
One Shot
Timing
Ground
Open Collector
Logic Output
Transistor
4152-01
Rev. 1.0.1