I'm analyzing the circuit in the picture below. I've read a little about unity gain amplifiers/buffers and think I understand the use of a single buffer. But I don't understand the purpose of having two buffers, one after the other.
Here are some more info about the circuit:
- OPAMPS: MCP6002, A and B are in the same package
- Input is from a 4 .. 20 mA signal (4 mA = 0.88 V at OpAmp-A's input, 20 mA = 4.4 V at OpAmp-A's input)
- Why have two buffers or what is the designer trying to avoid by using two?
- What is the purpose of the 4.7k and 1k resistors? I.e. what will happen if I change, lets say the 4.7k to a 1k?
- Same as question 2 but regarding the capacitances 100 nF and 10 nF