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I've designed this circuit in EasyEDA and first tried to simulate there also, but it didn't have subcircuits for any of the IC's.

Is there any simulation software that would simulate this circuit as it is? If not, are there generic equivalents of the components I could use for the simulation?

EDIT: I don't need to simulate the PIC, as it has a very simple and predictable program. I can just simulate it's output with a PWL source.

  • \$\begingroup\$ You are going to have trouble simulating the PIC, but you should be able to find SPICE models for the other components. \$\endgroup\$ – Caleb Reister Oct 10 at 16:19
  • \$\begingroup\$ I think Labcenter Proteus has a PIC simulator that'll run code, but (last I checked) their licensing was piece-meal for individual PIC families. Since it looks like RA5 is driving all of the IRS in parallel, simulate RA5 with a piece-wise voltage source or similar. Much faster to simulate, no complex license, and not locked in to Proteus. \$\endgroup\$ – rdtsc Oct 10 at 16:28
  • \$\begingroup\$ Your circuit appears to be over-engineered. Most commercial ESCs use a single gate driver to drive multiple FETs in parallel (with a separate Gate resistor for each FET). At 1-10kHz you probably don't need very fast transition times. \$\endgroup\$ – Bruce Abbott Oct 10 at 17:43
  • \$\begingroup\$ @Bruce Abbott There is a reason for it: This circuit will be made with a 1oz PCB and potted, so I'm trying to minimize heat. So I'm spreading the heat out on multiple components. There's one driver per FET so that I don't need any resistors in between, for the fastest switching time, again for minimizing heat. Even though just a few of the FET's and drivers could handle the current, then the copper traces become hot spots. So the design is really about minimizing heat, and spreading it out over a plane, rather than a few hot spot. \$\endgroup\$ – K0ICHI Oct 11 at 2:03

It might be difficult to find a one all solution that is easy to use. Analog simulations typically use SPICE code, and that means finding the files from each manufacturer and integrating them into a SPICE simulation

There are few mixed digital solutions, proteus is one of them and can simulate PIC's and SPICE code.. You'll most likely need to find models for each analog component you want to simulate.

If time is your interest, it's usually best to substitute a PWL file that represents the digital inputs and only simulate the analog sections in a spice programs such as LT spice. A PWL voltages is a a list of times and voltages that you can replicate digital signals with. This is how you would do this in LT spice

The other problem is there is not a spice file readily available from the manufacturer for the NCE0140KA, so a way to get around this is to find an equivalent mosfet with a spice file and simulate that, or to contact the manufacturer and ask for one.

Its usually best to simulate only after there is a proper design, and use simulation for verification. It's also a good practice to simulate only the sections of the design that aren't fully understood and are hard to work out on paper.


You show a PIC => driver > low RdsOn FETs (4) in Tandem acting as a low side switch.

Besides the parasitic inductance of your layout and total gate charge of the FET, it is basically an open-drain switch so the waveform depends greatly on your load Z(f) impedance , inductance back EMF etc. Thus accurate simulation is not possible.

The FETs here are low cost by volume and low RdsOn 14 typ 17 max mΩ @ Vgs=10V but take up space.

You may consider alternate NCh FETs that use 1 to replace these 4 with <5 mΩ @ Vgs=10V e.g. PSMN4R0-30YLDX

Examine similar Motor FET driver layouts for compact layouts and the replace four 3A Schottky diodes with one 20A TSP20U60S for overvoltage clamp on BEMF.

Keep power lines apart from signals at right angles and use twisted pair to reduce noise crosstalk.


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