Function generator is a very useful tool, especially when we are considering testing our circuit’s response to a certain signal. In this instructable I’ll describe the building sequence of small, easy to use, portable function generator.
Features of the project:

Fully digital control: No need for passive analog components.
Modular design: Every sub-circuit is a pre-defined easy to use module.
Output frequency: Available range from 0Hz to 10MHz.
Simple control: Single rotary encoder with built-in push button.
Li-ion battery for portable use, with external charging ability.
AC and DC coupling for output waveform.
LCD Brightness control for energy consumption reduction.
Battery charge indicator.
Digital amplitude control.
Three available waveforms: Sine, triangle and square.”

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