555 Timer problems in a circuit
Posted: Tue Sep 07, 2021 3:08 am
Hello, all
The c is a commonly used IC designed to produce a variety of output waveforms with the addition of an external RC network
For this little circuit, I'm using an Oscillator (parameter source: https://www.apogeeweb.net/circuitry/ne5 ... tions.html. Everything is well in the beginning. But it came out faulty after finishing.
With the collector unconnected the emitter (pin1 ) still sinks (20mA) and sources (30mA) current, when applying a square wave input. I measured mean dc amperage to either rail, so the max is higher. I cannot explain this behavior.
Doing the current measurement on the collector (pin 4) with an unconnected emitter I get 20mA when sinking, and none when sourcing. But not following the input signal.
Are there any suggestions for this? Many thanks.
The c is a commonly used IC designed to produce a variety of output waveforms with the addition of an external RC network
For this little circuit, I'm using an Oscillator (parameter source: https://www.apogeeweb.net/circuitry/ne5 ... tions.html. Everything is well in the beginning. But it came out faulty after finishing.
With the collector unconnected the emitter (pin1 ) still sinks (20mA) and sources (30mA) current, when applying a square wave input. I measured mean dc amperage to either rail, so the max is higher. I cannot explain this behavior.
Doing the current measurement on the collector (pin 4) with an unconnected emitter I get 20mA when sinking, and none when sourcing. But not following the input signal.
Are there any suggestions for this? Many thanks.