Hello!
I made up this circuit on a breadboard. I am using 20kHz PWM signal to switch it, which works fine. Resistive loads work nicely, but when I connect a DC motor to it, things go south.
Here you can see the circuit:
Hi,
See article on this site about the suggestion of using resistors.
" Discrete H-bridge Circuit For Enhanced Vibration Motor Control - Precision Microdrives "
Looks like the PWM drive pulses have the wrong timing.
What is your plan for "shoot-through"?
Keep in mind that highly trained EEs usually fail, and sometimes spectacularly, on their first few attempts at making H-bridges, which is why forum members strongly recommend to buy commercial H-bridge modules. They actually work!
Just checked with my oscilloscope the timings of the pulses on mosfet gates. They look good.
And resistive loads work good, and they don't have this weird stuff.
I tried to add Gate-Source resistors as @ruilviana advised, that didn't help
Would you be able to put one probe on the motor and one to measure one of the gates?
I made up this circuit on a breadboard.
That is the problem. The tracks have probably burned.
Breadboards are for low power logic circuits.
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