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10 years, 6 months ago.
ADC QUESTIONS plz comment if any one knws
can anyone explain what does 13mhz crystal and 200 khz sampling rate mean???
why 64 clocks per sample???
what if i have 1khz ac signal how to provide sampling rate ??
what is the maximum analog signal input frequency i can give?
what is the adc conversion time?????
i badly need to understand the basics anyone suggest a way????
2 Answers
10 years, 6 months ago.
200kHz sampling is the speed at which the ADC will do its conversions. If it needs 64 clock cycles to do a single conversion, then that requires to get a 200kHz sampling rate a 13MHz clock.
With a 1kHz AC signal you will at least require more than 2kHz sampling rate, but unless it cannot process it fast enough or you really want to go as low power as possible, it is alot easier if you go significantly above that.
8 years, 1 month ago.
Actually the manual states it's 65 cycles per conversion. This ruins timing (as you can't divide 96MHz by 65). It's also the reason you need 13MHz for 200kHz sampling rate.