I am trying to simulate a DC block circuit in PS PICE. I am using the following practical circuit link1:
I replaced the voltage to current section with the current source symbol given in PS pice. Please find the circuit diagram in the following link link2:
I have following questions
- How can I see the capacitor charging and discharging in PSPICE? I found the capacitor always charged whenever I run the simulations.
- What is the difference between voltage to current converter and constant current source? The INA circuit that I am using could be a constant current source ( plz. refer link1) and can be replaced with the current source given in PSPICE. I tried to use the PSpice models of INA and opa131 but did not work .
- I am trying to get rid of the DC leakage current produced by the INA 133 circuit using capacitors. I have discussed this issue in my previous post but need more advice! There problem is
a. At the power up the DAC outputs DC -2.5 volts. The inverting input of the INA133 is grounded and the 470uF capacitor is reduing the -2.5 volts to -0.5 volts accross the 384ohm resistor. There is a volage difference between the inputs which reflects at the output. I solved this problem partly by using the waveforms that ends at zero. So, after sending the waveform out of DAC, the DAC holds the zero and no more leakage. But at power up its an issue.
b. The leakage current is constant and I came up with the circuit that I mentioned in the link2 to get rid of it. Any comments!!