Tagged Questions

2
votes
2answers
102 views

What is the capacitor charging time when charged with a pnp current mirror circuit?

I want to use a 555 in monostable mode to make a ramp signal generator. The capacitor would be charged using a current mirror circuit. Given a input voltage, what would be the charging time of ...
1
vote
3answers
85 views

Identifying SMT element 331K

I am trying to repair a remote from a car lock. The symptoms are that a red led is lit longer than usual after button press and no respond from car lock. It works sometimes. The battery and ...
1
vote
1answer
138 views

Where to place a RC filter regarding decoupling capacitor?

I would like to add a low-pass RC filter (500Hz) to the power rail of a TLV2782 op-amp. Datasheet of TLV2782 recommends two decoupling capacitors: 0.1uF and 4.7uF and they are currently placed on the ...
7
votes
3answers
709 views

Capacitors and motors

Every RC car I've cannibalized has had a small ceramic capacitor soldered on to the contacts of the motors. What is the purpose of having this? What happens to the performance of the motor with out ...