# Need Help With Circuit Explanation

Discussion in 'General Electronics Chat' started by sonic007, Mar 28, 2012.

1. ### sonic007 Thread Starter New Member

Feb 26, 2012
11
0
I am a beginner Electronics enthusiastic and I am trying to build a circuit and I kind of know how to go about assembling the circuit but I do not understand purpose of some of components in the circuit. I have attached an image of the circuit for your reference.

- The Purpose of the 6.8k, 100 nF and 680k ?
- The Purpose of the combination of 100 nF and 680k in the first op-amp and 2nd op-amp ?

-The Purpose of the combination of 1uF and 68k ?

Also note shown on this circuit what will be the Purpose of a Comparator and how does it generate square pulse if attached to the two stage op-amp at the IC2 pin 7 ?

Thank you So much.

2. ### SlowCoder New Member

Mar 25, 2012
26
0
* watches with interest ... *

3. ### SgtWookie Expert

Jul 17, 2007
22,182
1,728
The opamps are configured as noninverting amplifiers. The 6.8k resistor is R1, the 680k is R2. The formula for the gain of a noninverting opamp with divided feedback is:
Av = (R2/R1)+1
This means that each stage has a gain of 101. Since you have two stages in series, and the gain of one stage is multiplied by the other, you will have a net gain of 101*101=10,201.