[info] high-side power switch

[AndreyB]

A board for PowerSSO-24 high-side switch by ST like VND5E025AK-E




https://svn.code.sf.net/p/rusefi/code/trunk/hardware/PowerSSO-24_breakout/

Could be used for hi-side alternator control and VTEC.

[AndreyB]

I am re-doing my own ECU based on the 0.4 revision and I want to put everything inside the case in the prototyping area (some stuff used to be hanging on the wires). The PowerSSO-24 power boards is just too large and we probably do not really need 43A output anyway?

I think we need a board for the smaller PowerSSO-12, for switches like VN5050AJTR-E or VN5E050AJTR-E

[Spilly]

I am re-doing my own ECU based on the 0.4 revision and I want to put everything inside the case in the prototyping area (some stuff used to be hanging on the wires). The PowerSSO-24 power boards is just too large and we probably do not really need 43A output anyway?

I think we need a board for the smaller PowerSSO-12, for switches like VN5050AJTR-E or VN5E050AJTR-E

Here is a board for the PowerSSO-12. https://oshpark.com/shared_projects/kpYpQ1tg

If the goal is to switch VTEC, alternator charge, and other devices that are well below the 27A overcurrent protection rating, I recommend going with a much lower overcurrent protection rating. Before the device goes into overcurrent mode you will most likely melt the factory wiring (for stranded conductors, 27A needs 6 AWG at minimum).

Let me know how you want to proceed.

[AndreyB]

Looks like we can get a bit smaller board without much change in the functionality. Larger heat sink holes would allow to get 0.4mm soldering wire in there - like on https://www.oshpark.com/shared_projects/OChRKHDe which I think is https://svn.code.sf.net/p/rusefi/code/trunk/hardware/DDPAK_breakout/

[Spilly]

Looks like we can get a bit smaller board without much change in the functionality. Larger heat sink holes would allow to get 0.4mm soldering wire in there - like on https://www.oshpark.com/shared_projects/OChRKHDe which I think is https://svn.code.sf.net/p/rusefi/code/trunk/hardware/DDPAK_breakout/

Is there a specific dimension you have in mind?

I didn't think about people hand soldering these. I will update the design.

[AndreyB]

19.79x21.69 mm-ish? that's a totally random number, that's the DDPAK board dimensions. 20x22mm to make it even?

I need to double-check how much vertical space is inside this mazda case, I am planning to mount it vertically with a couple of 90 degrees pins. BTW would be nice to have unused/mounting/non-signal holes on both sides of signal holes, this case I can have three wires for signal coming right from this little board, and other holes used to mount.

[Spilly]

19.79x21.69 mm-ish? that's a totally random number, that's the DDPAK board dimensions. 20x22mm to make it even?

I need to double-check how much vertical space is inside this mazda case, I am planning to mount it vertically with a couple of 90 degrees pins. BTW would be nice to have unused/mounting/non-signal holes on both sides of signal holes, this case I can have three wires for signal coming right from this little board, and other holes used to mount.

Ok I think I have a grasp on what you are wanting.

Do you want the board to use any type of terminals for input/output connections, or do you plan on soldering wires directly to the board?

[AndreyB]

Do you want the board to use any type of terminals for input/output connections, or do you plan on soldering wires directly to the board?

Just solding. Solid wires for signals, 18-20 ga wires for power lines, 0.052 inch diameter works good for 20 ga

Failing to read what we use for heat sink holes, a bit less then 0.052 inch.

[Spilly]

Do you want the board to use any type of terminals for input/output connections, or do you plan on soldering wires directly to the board?

Just solding. Solid wires for signals, 18-20 ga wires for power lines, 0.052 inch diameter works good for 20 ga

Failing to read what we use for heat sink holes, a bit less then 0.052 inch.

I will happily find you an IC that is similar to the VN5E050AJ-E but has a more appropriate overcurrent rating. If the VN5E050AJ-E is the only overcurrent device in the circuit and 18 gauge wire is the only conductor, it is highly likely that the wire's insulation, and anything else close by, is going to catch on fire.

[AndreyB]

I am all for a lower over-current protection, 27A is at least three times more then what is needed.

[Spilly]

What do you think about this?

https://oshpark.com/shared_projects/pz6SVaJU

[AndreyB]

https://svn.code.sf.net/p/rusefi/code/trunk/hardware/rusefi_lib/VN750PS-E.kicad_mod commited to rusefi_lib folder
schematics and board commited to https://svn.code.sf.net/p/rusefi/code/trunk/hardware/HighSideSwitch/

Still need to resolve paths in the project, and btw I've ordered the board some time ago.

[AndreyB]

Wrong package, not sure if the heatsink holes were supposed to be not aligned, not sure why these squares above the 0.1 pitch holes.

[AndreyB]

Wrong package

Ops, looks like I've got the wrong part Now I need to order http://www.digikey.com/product-detail/en/VN750PSTR-E/497-13814-1-ND/4214669

[Spilly]

That is my fault for not mentioning what IC to use. VN750PS-E seemed to be most appropriate the task. There are several other high side drivers, both lower and higher current ratings, in the 8-SO package.

The thermal vias are indeed supposed to be offset. The VN750PS-E does not have a thermal pad on the underside (not necessary due to less power dissipated by IC). Thus, the thermal vias are an attempt reduce thermal resistance between both sides of the board. The 12V connections have copper pours on both sides of the board.

I was using the squares above the 0.1" holes as a layout aid, and they can be removed. I will update the design to omit the squares.

[AndreyB]

Just for the record, for Dodge Neon 2003 alternator I was using this with MCU GND wire not connected, "TBD" R101 was somehow 120R (not connected so does not matter), and these wires sure look scary so I will go solder them a bit better.

[AndreyB]

What do you think about this?

https://oshpark.com/shared_projects/pz6SVaJU

Just realized it's 0603. All the stuff I have is 0805, will try fitting 0805 components. Still fighting with the project files - something is off with library paths and something is strange with Diode symbol and the PCB file does not open for me Just fixed one path at https://svn.code.sf.net/p/rusefi/code/trunk/hardware/HighSideSwitch/ but the diode is still not happy, it could be that we are on different versions of KiCad and this causes the issue?

[AndreyB]

Speaking of which I've extracted part of http://rusefi.com/wiki/index.php?title=Manual:Hardware into http://rusefi.com/wiki/index.php?title=Manual:Hardware:PCB_design_rules

[kb1gtt]

Not sure why the split of of wiki pages. I had it all on one such that you had pretty much all the design criteria on one page, which could be printed out on one page. It's not a big deal. I kind of wonder if the board specific stuff should have been on a different page.

[Spilly]

It's been awhile since I have played with the SVN software. Attaching a patch that should fix the file paths. Hopefully I did this correctly.