VFC110: Single Chip High-Frequency Voltage-to-Frequency Converter (VFC)

Using VFC110 chip, we can build a high frequency voltage-to-frequency converter. The features of this chip include the capability of high frequency operation, disable function, and an on-board precision 5V reference. This precision reference can be used to provide reference for offsetting the VFC transfer function, as well as provide transducer or bridge excitation. As well as shutting off the single VFC chip, Multiplexing several VFC outputs can be done by the enable function. The output is an open collector stage that is compatible with TTL or CMOS logics. Here is the schematic diagram of the circuit:

You can see that this circuit only use a pull up resistor for the output and two bypass capacitors for power supply filtering. You can use a 100nF mylar cap for these two bypassing capacitors. Using minimum the component count, this circuit provide 0-4MHz output for 0-10V input voltage. [Circuit’s schematic diagram source: Texas Instruments Application Notes]