Voltage to Frequency Converter ICL8038

This circuit is alternative approach to same solution show in earlier post. Here i have put the complete circuit in PNG format. 8038 is a marvelous chip, a custom monolithic analog computation unit, a device popular around the 80s, it was far ahead of its times indeed.

Now its availability and application are much reduced. Intersil made Popular Analog ASICs, the word ASIC itself came much later. They were also early in making low power cmos, this was at a period when microprocessor system consumed a lot of power and microcontrollers had just started coming in.

This was a small circuit made for driving an Impact counter. The heart being ICL8038. It must have been a Motor driving a Conveyor, the motor has a feedback attachment called Tachogenerator.

Only part of the circuit is shown here. See the image of product here Tacho Counter. The configuration is derived from the Application Notes of Intersil. The Voltage from Tachogenerator is Measured on a DPM-DVM and also fed to this circuit after attenuation and filtering.

Function Generator using ICL8038.

The square pulses of 8038 is used to derive a Logic pulse train for a CD4040. The CD4040 works of 0 and 12V. The above circuit is on +12 and -12. That is the reason R10-R15-Q1 are used. The pulses are 0-12V pulses. The Zero is Virtual like the Virtual Ground in low current power supplies.