Need a precise frequency difference culculation CMOScircuit

[kumarghz]

Friends,,
I Need a precise frequency difference culculation circuit, a simple design in CMOS technology. The circuit which should have output (Fout) as function of 2 input frequency, F1 & F2. Fout =|F1-F2|. Assume that Fout, F1 & F2 has 50% duty circle. Please help. Thank you.

 

[JoannesPaulus]

you could use two counters, c1 and c2, at a known reference frequency and see how many counts c1 and c2 make in a set amount of time.

 

[kumarghz]

Re: Need a precise frequency difference culculation CMOScirc

Thank you for the advice.
But I rather looking for much simple circuit. I wonder could that be possible with circuit like mixer,comparator or with few pieces of CMOS.

 

[jecyhale]

Re: Need a precise frequency difference culculation CMOScirc

Friends,,
I Need a precise frequency difference culculation circuit, a simple design in CMOS technology. The circuit which should have output (Fout) as function of 2 input frequency, F1 & F2. Fout =|F1-F2|. Assume that Fout, F1 & F2 has 50% duty circle. Please help. Thank you.

Mixer can be used. Just use F1 and F2 as the two input of Mixer, and the output is the result you need.