AVR DDS signal generator V2.0

Finally, the second version of the improved AVR DDS signal generator is here. First AVR DDS V1.0 generator was only an attempt of running the DDS algorithm without any analog amplitude control. In this DDS generator version, I still wanted to keep things as simple as possible using a minimum count of widely available components in the updated circuit. Also, I kept a single-sided PCB approach. AVR DDS specification AVR DDS signal generator V2.0 is a firmware-based DDS signal generator which uses slightly modified Jesper’s mini DDS algorithm which was adapted to AVR-GCC C code as in-line ASM. The AVR DDS signal generator has two outputs – one for DDS signal and another for high speed [1..8MHz] square signal – which may be used for reliving microcontrollers with wrong fuse settings or for other purposes where a high-speed square signal may be needed. High speed (HS) signal is output directly from the Atmega16 OC1A(PD5) pin. The DDS output is used for all complex signals that are generated via R2R resistor network and is adjusted via LM358N offset and amplitude regulating circuits. Two potentiometers can control offset and amplitude. The offset can be controlled in range +5V..-5V while magnitude in range…

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AVR DDS signal generator V1.0

Sometimes when tuning various electronic hardware, we need a simple signal generator with different waveform and frequency. One of the options is to by a professional with variable gain professional coating and many additional functions. But if you are an amateur, you might want to build one. This small project is dedicated to making one of those signal generators.  

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