J
john
- Jan 1, 1970
- 0
Hi,
I am trying to simulate a DC block circuit in PS PICE. I am using the
following practical circuit
link1:
http://profile.imageshack.us/user/ai466/images/detail/#69/circuitdiag...
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:
http://img253.imageshack.us/my.php?image=circuitdiagram2gl3.png
I have following questions
1. How can I see the capacitor charging and discharging in PSPICE? I
found the capacitor always charged whenever I run the simulations.
2. 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 .
3. 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!!
Regards
John
I am trying to simulate a DC block circuit in PS PICE. I am using the
following practical circuit
link1:
http://profile.imageshack.us/user/ai466/images/detail/#69/circuitdiag...
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:
http://img253.imageshack.us/my.php?image=circuitdiagram2gl3.png
I have following questions
1. How can I see the capacitor charging and discharging in PSPICE? I
found the capacitor always charged whenever I run the simulations.
2. 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 .
3. 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!!
Regards
John
