This project is an open source (hardware & software) DDS generator, based on: smart TFT module, AD9834, LM7171 fast amplifier. The homemade function generator is a quite common project on the internet. We can find different ways to do it:
– The quick & dirty way based on a DDS module bought on eBay
– The analog version based on a MAX038 / XR2206
– The clean way based on a FPGA and a fast DAC (e.g. http://www.circuitben.net/node/14)
– The software way (e.g. Arduino + R/2R DAC)
From my side, I wanted a small one which could fits my needs without being too expensive. According to me, such generator should at least:
– Be easy to use
– Output a signal from 1Vpp to 10Vpp (+/-5V), from 0 to 1MHz
– Have a low profile
– Without electric hazard (shall work on a 12V DC)
For more detail: Tiny DDS – Open source DDS generator
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