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Output Current

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New Member
I have a 555 timer circuit that is producing a rectangle wave, how do you test the output current of such a circuit ?



With an oscilloscope, or a true RMS multimeter. I don't know if true RMS meters works on square waves though, would depend on the meter. Alternatively if you know the duty cycle of the wave form and the load you can calculate the current yourself, just multiply the steady state current (force the 555 on to measure this with a meter) and multiply that by the duty cycle.
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New Member
Could you possibly put the circuit into a simulator (electronics workbench, Spice, etc) and get it to show you the waveform?

It would only be theoretical of course.


Well-Known Member
Most Helpful Member
For starters, read the datasheet. It talks about how much current the 555 can "source" and "sink" running on various supply voltages.
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