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homebrew controller parts
I had no luck with the cheap chinese driver boards so I decided to build Sean's H bridge.
I am struggling to source some of the parts, but managed to find alternatives.
In the schematic there is a TVS diode across the motor connections.
Can someone explain how to select the breakdown or zener voltage for this device?
Is it just a little higher than the motor supply voltage ?

you can build the controller without this diode, it is to protect the mosfets from transients.   It needs to be rated high enough to not  conduct in normal use, but low enough to protect the breakdown of the mosfets.   As for selection, I used 18 volt TVS for 12 volt controllers and 40 volt mosfets.  

Thanks Sean, i figured the built in diodes would protect the mosfets.
Found a 22V TVS, that'll do.
I finally got to put my homebrew controller together.
The bench tests look good using an industrial linear actuator.
Looking forward to do some testing on board.

Sourcing the right parts in small quantities was not easy in my country. ( NL)
So below is what I could find and used, might be useful for somebody.

I used IRFZ44N MOSFETS with IR2110 drivers.
For the MUR160 diodes I used SB260 Schottky diodes
I used a 14,4V  1500W TVS diode on the motor and 17 V on the 12V supply.
The 4,7uF foil caps are 400V and a bit bulky
Could not find a fast optocoupler, but did use a 4 channel level converter module.

Everything is on an 8x12 cm prototype board including Fuse holder, shunt, a Nano clone, 5V DC/DC converter and level shifter.
Used solid 1mm wire for the H bridge.

the mosfets you are using have a pretty high on resistance but should be ok.
The MOSFETS are IRFZ44NPBF,  94W with  a max Rds of 17.5 mOhm and 62nC  , I thought that was OK.

Dunno how to attach  photos, but a picture can be found here:
Yeah the mosfets are "ok" but when you can get mosfets with the same specs with rds on of 2.5mOhm the 44n seems obsolete.
Got a circuit diagram? Looks like something jlcpcb could make with many of the parts presoldered as surface mount.
I did not bother to draft a schematic, and used Sean's schematic together with the IR2110 data sheet.
I also did not design a pcb because most of my projects can be done on protoboards.
If anyone wants to do a PCB design I can do a schematic, but tbh I suck at KiCad.

As for MOSFET selection I saw that RS-online have a part selection tool maybe I can find one with 2.5 mOhm as Sean suggested.
give a go for schematics, jlcpcb is just a fantastic resource to get cheap boards made, or slightly less cheap if you don't want to wait for slow post.

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