Not sure which previous thread you are referring to, should give a link just in case. If it's related to shunt current measuring or PWM driver circuits, the new post should have been appended to the old thread.
A gate driver is suggested for fast MOSFET switching. Processor I/O pins aren't designed to drive multiple nF gate capacitance. Which gate driver impedance has been assumed in your switching loss simulation?
LM358 can be roughly considered a single supply OP. But the circuit requires the OP output to sink current through C6 at only mV output voltage, which isn't well managed by any single supply OP. The other question is what's the intended minimal measured current and current accuracy. OP offset voltage and output voltage range should be selected respectively. With LM358, the output voltage range towards negative rail might be improved by connecting a pull-down resistor in a 100 ohms range to the first stage output.
MCU_PWM_1 source isn't shown in the schematic, so it's reasonable to ask about the characteristic. If it's Arduino I/O, you should add something like 50 ohms port impedance in simulation. This will probably slightly increase switching losses, but I agree that operation at 500 Hz is possible without a dedicated gate driver. You should not reduce the gate series resistance considerably below 100 ohms, otherwise the ATmega maximum ratings might be exceeded.
A CMOS OP like LMC6482 has better sinking capability near the rails than LM358, offset error is however in a similar range.
I would rather use 50 mohm to reduce power dissipation, but it depends on your design preferences.
Input B of the TC427 gate driver should be grounded, do not let it floating.
How did you choose the 10 ohms resistor for the gate driver ?
Offhand I see no problem with your circuit.
If you wanted to save a little money you could use CD4050 buffer gates as a driver for the MOSFET.
You just tie all 6 inputs from one package together to the micro output and all the outputs in parallel to the MOSFET gate.
All the gates on one chip should switch sufficiently close together in time so there is no problem with tying their outputs in parallel.
Since your MOSFET is logic level, you can operate the CD4050 from 5V.
That should provide sufficient drive for the MOSFET at 500Hz.
Yes.If I only regulate the average current when the wire length changes, would I at least get roughly similar temperatures?
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