12$ 30MHz Signal Generator Using Arduino

Contents hide 1 Summary of 12$ 30MHz signal generator using Arduino

Summary of 12$ 30MHz signal generator using Arduino

This article details how to build a compact, affordable 0-30 MHz signal generator for $12 using an Arduino and an AD9850 DDS synthesizer module. The device outputs sine waves controlled via a rotary encoder, with frequency displayed on a 16x2 LCD. The AD9850 generates high-quality analog signals using direct digital synthesis, and while capable of up to 40 MHz, the project limits output to 30 MHz for stability. The circuit is simple, suitable for breadboard assembly or compact soldering, and powered by a 5V supply with under 270mA current.

Parts used in the 30 MHz Signal Generator Project:

• Arduino Pro Mini
• AD9850 DDS Synthesizer Module
• 16×2 LCD Display (Hitachi HD 44780)
• Rotary Encoder
• CP2102 USB to Serial Converter (or equivalent)

A signal generator is an electronic device that generates electronic signals and waveforms. These electronic signals are either repeating or non-repeating as per the requirements and field of applications. It is generally used in designing, testing, troubleshooting and repairing electronic devices. A signal generator can generate various kinds of waveforms. Most common are the sine wave, square wave, sawtooth wave and triangular wave.

This instructable shows a full guide on how to make a 30 MHz signal generator for 12$, using an Arduino and an AD9850 DDS synthesizer module. The circuit is pretty simple and small enough to fit in your pocket. Kedar Nimbalkar, the author of the instructable, says:

A precession signal generator is very easy and affordable to make using an Arduino and DDS synthesizer (ad9850) . It’s World’s first smallest portable signal generator.

You can make decent 0 -30 MHZ frequency Signal generator only in 12$ .

Parts List:

1. Arduino Pro mini2.AD9850 (DDS Synthesizer)3.16×2 LCD Display ( Hitachi HD 44780 )4.Rotary Encoder5. CP2102 (or any USB to serial converter)

I think you are familiar with all of the above items except the AD9850 (DDS Synthesizer). First of all, you need to know what does DDS stand for.

Direct digital synthesizer (DDS) is a type of frequency synthesizer used for creating arbitrary waveforms from a single, fixed-frequency reference clock. A basic Direct Digital Synthesizer consists of a frequency reference, a numerically controlled oscillator (NCO) and a digital-to-analog converter (DAC).

AD9850 (DDS Synthesizer):

The AD9850 is a highly integrated device that uses advanced DDS technology coupled with an internal high-speed, high-performance D/A converter and comparator to form a digitally programmable frequency synthesizer and clock generator function. When referenced to an accurate clock source, the AD9850 generates a spectrally pure, analog output sine wave. In a nutshell, AD9850 works on DDS (direct digital synthesis ) which can generate analog waveforms with digital input. 

Circuit Diagram Of Signal Generator:

The circuit diagram is very simple. You can make it on a breadboard, or just solder components end to end to make it more compact.

The Arduino sends digital signals to AD9850 and the module generates analog output Sine wave. The display, which is connected to Arduino, shows output frequency and step increment/decrement value. The rotary encoder is for changing frequency. Though the AD9850 module can generate up to 40 MHz frequency, but after 30 MHz the output frequency becomes unstable. So in this circuit, the maximum frequency is limited to 30 MHz.

You can make a decent 0-30 MHz frequency signal generator for only 12$ . If you are pro “overclocker”, then 40 MHz in same price .

The signal generator runs on 5 Volt power supply and current should not exceed 270mA.

Arduino Sketch:

The Arduino code is HERE.

Output:

Watch the video which demonstrates the 12$ signal generator.

https://youtu.be/1SgcjxacGlQ

 Source: 12$ 30MHz signal generator using Arduino