First of all, I am a newbie to avr. In fact I am new to microcontrollers itself. Whatever I have learnt is through various entries of this forum.
I require to use ADC of avr atmega32 to convert the output of a microphone signal. My signal is less than 2Khz and consequently I want a Nyquist frequency of 4Khz. I also require 8-bit resolution.
Now i need the system clock to run at 16 Mhz because after each ADC conversion I need more than 2400 cycles for execution of digital filters that i have programed into the microcontroller. These filters have to work in real time on each sample before the next sample comes in.
Now if i use a 16Mhz system clock with a 128 prescaler I get an ADC frequency of 125Khz and for free running mode the sampling frequency comes out to be 125Khz/13= 9615 Hz.
And at this frequency the no. of clock cycles between samples comes out to be 16000000*(1/9615)= 1664, which is significantly less than my requirement.
My question is if it is possible to get a ADC sampling frequency of around 4000Hz with a system clock of 16Mhz?
Please help me. I am in a bind here.
Also, i may have posted in the wrong place. In that case please guide me to the correct place.