Any component that relies on an electromagnet or coil of wire for its operation will be inductive, that is the nature of coils of wire. Common examples are relays, solenoid and most types of motor. It is standard practice to put a 'flyback' diode across any inductive load in order to catch the back…

This is the test circuit with a diode across the inductor: [Schematic with diode.jpg] This is the resulting oscilloscope trace: [With diode 4ms timebase.jpg] Note there are no high voltages or electrical noise, just the exponential decay of the current to zero. Also note that the voltage at th…

Occasionally I see comments in the forum suggesting that because some MOSFETs have a body diode between source and drain there is no need to put a diode across the inductive load they are driving. This schematic illustrates the situation, with the switch taking the place of the MOSFET and the 1N4004…

Introduction: The topic of flyback diodes came up in another thread (in which I had been trying to find out the specific reasons why the conventional wisdom is to not power a DC motor from Arduino 5V PIN — like this , for example). @PerryBebbington had pointed to this tutorial , and suggested that os…

Flyback diodes and why you need them

Other Hardware General Electronics

PerryBebbington January 28, 2023, 10:44am 7

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Flyback diodes and why you need them

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