Hello!
I'm studying for a test, and I wanted to make sure I'm trying to do this right, but I also don't know how to calculate a couple things.
I'm studying for a test, and I wanted to make sure I'm trying to do this right, but I also don't know how to calculate a couple things.
Given that R1=R4=R6=R7=100K, R2= 20K, R3=1K C2=10uF, C1=1000uF, C3=50pF and Vcc = 15V,
a. Draw the DC model for this circuit
This is what I get by changing the capacitors to open circuits:
b. Find the bias voltage at pin 6 of op amp U1.
Pins 2 and 3 of U2 are at 7.5 volts. The output voltage of U2 is also 7.5 volts, since pin 2 of U2 is connected to pin 6 of U2. This is connected to pins 2 and 3 of U1, which are both going to be 7.5 volts. Since both those pins are also connected to pin 6 of U1, the bias voltage is going to be 7.5 volts. PSPICE gives approximately the same answer, when I simulate the DC model of this circuit.
c. Find the low-frequency cut-off.
Am I correct in assuming that it's 1/(2*(Pi)*1000*0.000010) = 15.9155 Hz?
d. Estimate the voltage gain at 1KHz of the signal source V3 to R3.
Now here, I don't know how to calculate this. Simulating the circuit in PSPICE gives me a gain of 1.05 volts at 1 KHz, using the following values for V3:
Rich (BB code):
AC=1
VOFF=0
VAMPL=1FREQ=1KHz
e. What load does V3 see?
Power is voltage times current, but given the circuit, I'm kind of lost, even though it's probably something simple.
Thanks in advance for any help!