Electronics > Projects, Designs, and Technical Stuff

variable power supply circuit

<< < (6/8) > >>

xavier60:

--- Quote from: aneesh on June 18, 2020, 06:35:02 am ---yes thats what the circuit i attached above is similar, it also works in switching mode. its not on continuously . it switches the comparator checks the voltage and switches off till the output is stable.
dps 3005 also works the same way

--- End quote ---
You have forgotten to include your age in your profile.

The hand drawn design in the first post will operate as a linear regulator and likely an unstable one.
If you  want  to make a switch mode regulator, the best chance of success is with a self contained Buck IC like the LM2596.
Without an oscilloscope you will be working in the dark were SMPS is involved.

aneesh:
yes i want to build linear supply which works with power transistors but why does it become very hot with mosfet.
some manufacturers have achieved good results with mosfet.
let me be clear is it because of high freq, duty cycle or turn on or off cycle because of gate source resistor

mikerj:

--- Quote from: aneesh on June 18, 2020, 06:35:02 am ---yes thats what the circuit i attached above is similar, it also works in switching mode. its not on continuously . it switches the comparator checks the voltage and switches off till the output is stable.
dps 3005 also works the same way

--- End quote ---

Your circuit is a linear regulator, NOT a switching regulator.  Which part of your circuit do you think provides the PWM waveform for driving the MOSFET?  Where is your inductor and freewheel diode?

aneesh:
yes linear regulator but if you see its the opto pulses which switches the transistor on/off but i think am i not switching it on and off properly.
i have attached a ref circuit of another manufacturer.

kallek:
You can't beat Ohm's law! Unregulated voltage minus output voltage is turned heat in mosfet! Mosfet is doing it's stuff to work as resistor!

Navigation

[0] Message Index

[#] Next page

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod