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Dear Experts

,This is my circuit diagram,

I am Using


2. MOSFET ( 47N60C3

)I have a problem is the circuit sir,

it works better with 10 Ohm resistive load but when I connect an inductive coil (which has very less resistance and homemade using coils) and a free-wheeling diode across it,

I am facing a problem

Problem: Power supply is in constant current mode at most of the time and 5A and 8V drop which is the max that I can achieve my power supply is 30V, 5 Amp power supply

Requirement: 12V-15V drop at 1-3Amps

what could be the necessary arrangements to achieve

what are the possible ways to achieve this?



23 days ago

I have a push button on/off switch that connects to 12v power, then to a momentary switch, then to LED strips. Currently when I plug in power the LEDs come on and will go off when I use the on/ff switch. They also turn off when I hold the momentary switch down. I need it to be the opposite, when the momentary switch is held the lights should come on. This is going inside a 3D printed sword stand so the objective is to have the sword depress the momentary switch and turn the lights on. If the sword is removed then the lights will turn off (Switch is no longer pressed). The on/off button is there so if the user wants to leave the sword in the stand but have the lights off they can do that without having to remove the power cord.

Jack A Lopez

27 days ago

It is not obvious to me what you are trying to do here.

It kind sounds like you are powering this thing with one of these bench style power variable power supplies; i.e the kind with two knobs: a voltage limit and a current limit, and also with two little indicator lights: CC and CV, which tell you what mode the supply is operating in, either constant current (CC) or constant voltage (CV).

Using just a piece of wire as the load for your circuit causes too much current draw?

I dunno. That does not seem surprising to me. I mean, big current draw is the expected result when connecting a short, or something approximating a short, across the output of something.

If this length of wire is supposed to be an inductor, maybe it needs more inductance? Like, maybe it needs more turns? Or a ferromagnetic core? Or something? Maybe the signal driving it needs to be faster, so the inductance is more reactive, offers more impedance, at that (higher) frequency.

Regarding current, what are some things that can be done to give you more current?

Perhaps a large capacitor wired across the points you call +DC and -DC. That could maybe help deliver some transient, instantaneous, current right to the load.

However, it won't help if the time-averaged current is too large. You know, if this thing just wants big current, pretty much most of the time.

Also regarding time, maybe if you reduced the duty cycle to this MOSFET, so it turned on less of the time. Perhaps that would lower the time-averaged current draw.

Or maybe you need a bigger, more beefy, power supply, because whatever you are driving truly needs MOAR POWER!

Like I wrote at first, I am not sure what your circuit needs, because I am not sure what you're trying to do.


27 days ago

Also, be aware that switching inductive loads will create voltage spikes in the many 100V to many 1000V region!
This can easy kill your electronics! Always (!!) add a free wheeling diode / flyback diode to an inductive load.


4 weeks ago

Your voltage breaks down if the load is too high.
It does not matter that your supply could provide 30V in this case.
What is the DC resistance and the AC resistance (at the switching frequency) of your work coil?