Hi there,
I've recently started pursuing electronics as a hobby, but I'm having some trouble with the classic astable multivibrator circuit.
I think I understand how the circuit works, but I'm confused by the capacitors C1 and C2 as people seem to be saying that it's ok to use electrolytic capacitors as long as they are polarized as shown in the diagram.
Referring to the diagram, if Q1 is conducting (and the circuit has been running for several cycles), the voltage on the left plate of C1 will be about 0.1V (because Q1 is saturated). The voltage on the right plate of C1 will initially be -4.3V and will rise to around 0.6V before the Q2 base starts conducting and the Q1 base stops conducting, etc.
My problem with this is that there is a time when the right hand (negative) plate of capacitor C1 is at 0.6V and the left hand (positive) plate of C1 is at 0.1V. I think that the capacitor is then reverse biased.
As I mentioned, I'm new to the field, but I've seen endless warnings about reverse biasing electrolytic capacitors. My question is as follows:
Is it ok to reverse bias an electrolytic capacitor as long as the voltage across it is low, or should you really not be using electrolytic capacitors for this circuit?
I don't have much experience with circuits like this yet and would greatly appreciate some advice.
Thanks, Ben
I've recently started pursuing electronics as a hobby, but I'm having some trouble with the classic astable multivibrator circuit.
I think I understand how the circuit works, but I'm confused by the capacitors C1 and C2 as people seem to be saying that it's ok to use electrolytic capacitors as long as they are polarized as shown in the diagram.
Referring to the diagram, if Q1 is conducting (and the circuit has been running for several cycles), the voltage on the left plate of C1 will be about 0.1V (because Q1 is saturated). The voltage on the right plate of C1 will initially be -4.3V and will rise to around 0.6V before the Q2 base starts conducting and the Q1 base stops conducting, etc.
My problem with this is that there is a time when the right hand (negative) plate of capacitor C1 is at 0.6V and the left hand (positive) plate of C1 is at 0.1V. I think that the capacitor is then reverse biased.
As I mentioned, I'm new to the field, but I've seen endless warnings about reverse biasing electrolytic capacitors. My question is as follows:
Is it ok to reverse bias an electrolytic capacitor as long as the voltage across it is low, or should you really not be using electrolytic capacitors for this circuit?
I don't have much experience with circuits like this yet and would greatly appreciate some advice.
Thanks, Ben