- #1
edmondng
- 159
- 0
Need some help or suggestion here.
I'm trying to collect some data resulting from very small changes. What i want is for example a change from 40pF to 40.5pF to result in a bigger voltage change say 0.5V to 0.8V, enough for me to see some difference. In other words, a very big SNR.
The way i have my setup now is using a cap reference and comparing it with the variable, and going through a differential amplifier.
I was thinking in the sense of circuit manipulation where for example if you have 2 caps in series, where 1 is very very large like 1000pF and the variable cap is only 40pF, Then the resulting capacitance from 40pF to 40.5pF will result in only a very small change.
Same is true for resistance in parallel. Put a 52 Ohm in parallel with 1100 Ohm, but now change the 52 to 53 ohm and the resulting signal is still small. So is there some way for me to manipulate such that i can get a bigger signal change with my small input change.
Ideas, suggestion would be great. Thanks
I'm trying to collect some data resulting from very small changes. What i want is for example a change from 40pF to 40.5pF to result in a bigger voltage change say 0.5V to 0.8V, enough for me to see some difference. In other words, a very big SNR.
The way i have my setup now is using a cap reference and comparing it with the variable, and going through a differential amplifier.
I was thinking in the sense of circuit manipulation where for example if you have 2 caps in series, where 1 is very very large like 1000pF and the variable cap is only 40pF, Then the resulting capacitance from 40pF to 40.5pF will result in only a very small change.
Same is true for resistance in parallel. Put a 52 Ohm in parallel with 1100 Ohm, but now change the 52 to 53 ohm and the resulting signal is still small. So is there some way for me to manipulate such that i can get a bigger signal change with my small input change.
Ideas, suggestion would be great. Thanks