Expansion board with Analog-digital interface enables transition of analog signals to the FPGA circuit where digital processing of signals is implemented. We developed an expansion board with circuits for analog-digital and digital-analog conversion. We made logic for controlling converters and saving data in an FPGA circuit. Data acquisition runs through the serial peripheral interface (SPI) and is realized with MAX11105 (which converts analog signal to digital - ADC) circuit. The digital signal is then saved in an FPGA circuit made by the Altera corporation, from the Cyclone IV series, which can be modified and read. The digital signal in transferred through the SPI interface with the AD5451 (which converts the digital signal the to analog - DAC) circuit on the output as an analog signal.
We made a prototyping expansion board for testing and measurement and a final expansion board where we upgraded the circuit. We added an SMA connector for the ability to connect to the expansion board thruough a cable and a 2x6 PMOD connector for connecting the printed circuit to the programmable circuit DE0-Nano.
During measurements on the final development board, we achieved minor deviation of sampled signal and tested the circuit response to the sine signal input.
|
