The KA331 is a Voltage to Frequency Converter provides the output pulse train at a frequency precisely proportional to the applied input voltage. The KA331 can operate at power supplies as low as 4.0V and be changed output frequency from 1Hz to 100kHz. It is ideally suited for use in simple low-cost circuit for analogue-to digital conversion, long term integration, linear frequency modulation or demodulation, frequency-to-voltage conversion and many other functions. This product is general usage and suitable for many different applications.