So what I'm trying to do is build a current-to-voltage converter for the purpose of measuring the input alternating voltage signal and output current of a dielectric sample in series with an op-amp. The circuit can be found here at page 11. http://interactive.npl.co.uk/multiferroics/images/7/7a/CMMT_A(152).pdf
Just a note that I don't have much electronics background, very limited in fact, and what you see here is my attempt at replicating a circuit.
For this circuitry, I will be applying an AC voltage of 20Vpp to 100Vpp at a maximum frequency of 200kHz. The sample I will be using is a Piezoelectric material with about 400pF capacitance. My voltage supply will be from a signal generator connected to an amplifier whose output is a BNC. And for recording the signals, I will be using passive scope probes.
The questions I have are:
1. What op-amps are suitable for what I am trying to achieve? It is stated that a 741 op-amp is suitable. What are better alternatives?
2. Am I right in saying that input power supply for the op-amp is unnecessary?
3. The drawing shows a virtual ground but how would the circuitry be wired up? I am guessing that the ground output (shielding) from the BNC connector connect to both the '+' and 'output' terminals on the op-amp?
And the +/- output from the BNC connect to the ' - ' terminal on the op-amp... correct?
4. Since I will be using passive scope probes. At which points in the circuitry do I connect the probe for the Vout signal? Would it be the output terminal of the op-amp?
Just a note that I don't have much electronics background, very limited in fact, and what you see here is my attempt at replicating a circuit.
For this circuitry, I will be applying an AC voltage of 20Vpp to 100Vpp at a maximum frequency of 200kHz. The sample I will be using is a Piezoelectric material with about 400pF capacitance. My voltage supply will be from a signal generator connected to an amplifier whose output is a BNC. And for recording the signals, I will be using passive scope probes.
The questions I have are:
1. What op-amps are suitable for what I am trying to achieve? It is stated that a 741 op-amp is suitable. What are better alternatives?
2. Am I right in saying that input power supply for the op-amp is unnecessary?
3. The drawing shows a virtual ground but how would the circuitry be wired up? I am guessing that the ground output (shielding) from the BNC connector connect to both the '+' and 'output' terminals on the op-amp?
And the +/- output from the BNC connect to the ' - ' terminal on the op-amp... correct?
4. Since I will be using passive scope probes. At which points in the circuitry do I connect the probe for the Vout signal? Would it be the output terminal of the op-amp?