I have designed a 10-bit SAR ADC. Now I need to measure the PSRR performance of the ADC.
I read some articles. It says I will need to inject a 100mV sine wave to the power supply and ground the input. Capture the output code and process it with FFT. I have done so and get a spur of -72dB at 1kHz (the supply noise is 1kHz). May I know how to calculate the PSRR in this case?
howardtang85,
you must also inject the 100mv signal only to the ADC input and measure its power using fft method, then subtract result of the first measurement from second.