Multi-Channel Programmable Frequency Generator

Paul Chilton Technical

2013-01-10 16.10.44

We have been working on a project that requires a device to be driven with 16 sine waves. Each channel needs to have programmable frequency and amplitude. Labman have designed a PCB based around Analog Devices AD9835 Direct Digital Synthesizer. Our module is capable of driving all 16 sine waves simultaneously while keeping them all perfectly in-phase.

Specifications:

  • 10-bit DAC output stage
  • Frequency Range: 1kHz – 10MHz
  • Amplitude Range: 0V – 10Vp-p
  • 32-bit frequency selection
  • 50dB SNR

FFT of Frequency Generator

The image to the left shows the FFT of the output signal from the generator. The signal has a signal to noise ratio of 50dB. The large peak on the left is a 100kHz sine signal, the mid peak is the 50Mhz clock feedthrough. The third peak is the second harmonic of the clock at 100Mhz.

 

More pictures of the full 16 channel module coming soon…