Hello All,
I'm trying to use the 33210A signal generator to determine SNR loss of an ADC with poor PCB layout. The ADC's SNR from datasheet is 85dB and my measurement shows 70dB. I need to determine how much from that 15dB difference is on the ADC side and how mych comes from the generator itself. In order to do that I obviously need to know what's the noise of the generated signal. I don't have access to any equipment to measure the generator's output signal noise or SNR. Is there any way to determine that from the information from the generator's datasheet? Signal that I'm using is 1.4V of 100Hz sinewave and my final measurement bandwidth is 6kHz.
I'm trying to use the 33210A signal generator to determine SNR loss of an ADC with poor PCB layout. The ADC's SNR from datasheet is 85dB and my measurement shows 70dB. I need to determine how much from that 15dB difference is on the ADC side and how mych comes from the generator itself. In order to do that I obviously need to know what's the noise of the generated signal. I don't have access to any equipment to measure the generator's output signal noise or SNR. Is there any way to determine that from the information from the generator's datasheet? Signal that I'm using is 1.4V of 100Hz sinewave and my final measurement bandwidth is 6kHz.
I set up the 33220 to put out 0 dBm (about 447 mVpp) at 5 kHz into a PSA.
Then I asked the PSA to measure noise in 1Hz bandwidth at 6 kHz (1 kHz higher, and 1 Hz wide) to
measure noise floor. The PSA says the noise has an amplitude of 476 nanoVolts.
Since you want a bandwidth of 6 kHz, we need to multiply this by square root of 6 kHz = 77.46
so 476 nV * 77.46 = 36.9 microvolts. So signal = 447 mV, noise = 36.9 uV do the SNR would be 447m/36.9u = 12416
or about 82 dB SNR in the 6 kHz bandwidth
Let me know if that helps. This is only a sample size of 1. I am not an SNR expert so hopefully that all looks correct to everybody.