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Can a short circuit be used in a power supply?
This instructable is about a universal short circuit protection that I’ve designed to use in bench power supplies. I’ve designed it to fit in most power supplies circuits. In order to this circuit fit in your bench power supply, you will need to do some calculations, but don’t worry, I’ll explain everything on the next steps.
What should be the output current of a power supply?
If the output current of your power supply is higher than 2A, you should reinforce the lines of the series resistor and relay. See the attached PCB picture for more information. To turn this circuit on, you will need to supply it a voltage that can be from 9V to 15V.
Why do we need an amplifier in a short circuit?
As the voltage drop on the resistor in series with the power supply is too small, we need to amplify it a little bit because some op amps are not too accurate when comparing low voltages like 0,5 volts or lower. And that’s why the first stage (stage 1) of this circuit is an amplifier using another op amp.
How to choose a resistor for a power supply?
You need to choose a resistor that the voltage drop on it is around 0.5~0.7 volts when the overload current is passing through it. The overload current is the point that the protection circuit actuates and shuts down you power supply output to prevent damage on it. You can choose a resistor by using ohms law: V=R*I.
How to design a simple power supply circuit?
Let’s begin and learn how to design a power supply circuit, a simplest one first , probably for the noobs who would find this information extremely useful. A basic power supply circuit will fundamentally require three main components for providing the intended results.
Can a Class 2 power supply be used?
The AHJ inspector does not have to accept the components in safe NEC Class 2 control circuits (UL 508 § 2.7) which is why non-listed UL devices may also be used. On the other hand, components with the approval “…for use with Class 2 only…”
How many amps can a power supply circuit handle?
A few power supply example circuits using this IC Since the above IC can only support a maximum of 1.5 amps, for greater current outputs another similar device but with higher ratings may be used. The IC LM 338 works exactly like the LM 317 but is capable of handling up to 5 amps of current.