Simple Sine Wave Generator With Pro Mini

This instructable shows you how to:

1. Program Arduino Pro Mini (ATMega328P) with Arduino Uno Board without removing the ATMega chip

2. Generate a pure sine wave with fixed frequency and minimal components.

Disclaimer: Code used is not made by me. The author is mentioned in the sketch.

Arduino boards used are clones. (Yeah, i know... I should donate).

Step 1: Upload Sketch to MiniPro With Arduino UNO Board

For uploading the sketch:

>Create a folder named "Waveforms" in ..."\Arduino\libraries\" and copy the heather attached named sinewavedata.h (default path "C:\Program Files (x86)\Arduino\libraries\Waveforms");

> Download the sketch and open.To change frequency, observe line "#define SAMPLE_RATE";

>Change device to Pro Mini from Tools > Board: > "Arduino Pro or Pro Mini" (or you can upload sketch to UNO as usual);

>Connect pin-to-pin RX, TX, Vdd=5V and GND from Arduino UNO board to ProMini board (as in image);

>Hold reset button on ProMini pressed and hit Upload;

>When status says: " Uploading..." release the reset, then you should have "Done uploading."

Now, your Pro Mini should generate a wave on pin 6 ( example in capture attached is 50Hz).

Step 2: Filtering Sinewave

To filter the sinewave you need a low-pass filter.

For 50Hz, I used a 470uH inductance and a 2.2uF capacitor (see schematic in image attached).

Supply 5V to Vdd pin, connect GND and it's done. Now you have a sinewave generator.