Digitally programmable voltage-to-frequency converter

The author presents a novel design approach for a VFC (voltage-to-frequency converter) based on a digital technique which utilizes an analog-to-digital converter, programmable read-only-memory, latch, divide-by-n chip, and associated control circuitry. The unique aspect of this design is the fact that the ratio between the maximum and minimum frequency rates is programmable by the user, and the performance is highly repeatable. This technique was developed in order to provide a drive circuitry for a 5-b digital phase shifter which was being serrodyned in order to create deception jamming functions for electronic countermeasures applications. A circuit diagram of the digital VFC is presented.<>