I would like to DC bias an AC signal using a voltage divider as shown in the following schematic. I realise the bias point would be subject to noise from the power rails, but that is not a concern for this application.
I understand that C1 and R2 (and possibly R1?) would form a passive high pass filter. I am familiar with the calculation for a high or low pass filter involving a single capacitor and resistor but am unsure how to proceed when two resistors are used as shown.
Assuming only C1 and R2 were present, the cutoff frequency f = 1 / (2 Pi R C) = 159 Hz. Could you give me a hint what to do next when R1 is included? This is NOT a homework question.
Just for your reference, I have already considered answers to these questions:
Based on this comment:
"For signals all voltage sources have a resistance of 0 Ohms, so the both resistors are effectively in parallel. – Tom Kuschel 3 mins ago"
would it be correct to redraw the circuit as follows?
The parallel resistance (10K || 10K) could then be calculated as 5K.
f = 1 / (2 Pi 5*10^3 100*10^-9) = 318 Hz