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Can I use a resistor instead of a diode?
Using a resistor instead of a diode is one of those entertaining tradeoffs. A diode will limit the switch voltage to only a bit over the source voltage. This is extremely useful when the switch is a solid-state device such as a MOSFET which absolutely cannot handle kV spikes.
What is a flyback resistor?
Flyback diodes are commonly used when inductive loads are switched off by semiconductor devices: in relay drivers, H-bridge motor drivers, and so on. A resistor in series with the diode will make the circulating current decay faster at the drawback of an increased reverse voltage.
How do you make a small resistor?
To create a resistor with a small resistance (or Ohm) value, use a thicker, shorter wire as the path between the two electrical leads. To create a resistor with a larger Ohm value, use a thinner, longer wire.
Why do you need a flyback diode in a relay?
The use of a diode in a relay circuit prevents huge voltage spikes from arising when the power supply is disconnected. A flyback diode is sometimes called flywheel diode, freewheeling diode, relay diode, or snubber diode as a flyback diode circuit is a type of snubber circuit. Why Put a Diode Across a Relay Coil?
When to use a resistor instead of a diode?
Using a resistor instead of a diode is one of those entertaining tradeoffs. A diode will limit the switch voltage to only a bit over the source voltage. This is extremely useful when the switch is a solid-state device such as a MOSFET which absolutely cannot handle kV spikes.
What should the reverse voltage of a relay be?
In your relay, the coil current is shown as 79.4 mA. Specify a diode for at least 79.4 mA current. In your case, a 1N4001 current rating far exceeds the requirement. The diode reverse voltage rating should be at least the voltage applied to the relay coil. Normally a designer puts in plenty of reserve in the reverse rating.
When does a flyback occur in a circuit?
Voltage spikes are fast, short-duration electrical transients in voltage in an electrical circuit. Flyback occurs when there is an abrupt voltage spike across the inductive load when the supply current is abruptly reduced or interrupted. Flyback occurs due to electromagnetic induction.