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Re: VW Golf -89 Street/Trackday Car with ELMicro CardS12
Posted: Mon May 27, 2013 10:05 pm
by Fred
Congratulations, but let's save the chatter about that for the real thread ;-)
Neat picture! DIY to the core/for life! :-)
Fred.
Re: VW Golf -89 Street/Trackday Car with ELMicro CardS12
Posted: Mon May 27, 2013 11:04 pm
by Fred
viewtopic.php?f=55&t=2145 < this one, this one!!! :-)
Re: VW Golf -89 Street/Trackday Car with ELMicro CardS12
Posted: Wed Jun 26, 2013 1:29 pm
by MrOnion
I have done some driving with the onionboard and so far it has been working ok. A little setback happened as I used the board with a separate mains power supply at home and overheated the regulator a few times. This is most probably caused by oscillation that is happening because of too small capacitors and/or capacitors being too far from the regulator. The home supply might have given some voltage spikes that drove the regulator insane as I haven't had any problems in the car.
To correct the issue I tweaked the proto pcb a little. I removed the 0.1uF ceramic cap after the regulator and soldered it straight to the regulator legs. I also lied to you a little (blog text) and had an 10uF cap after the reg (datasheet said it should be enough) so I installed a 22uF cap where the ceramic was. If I still get problems 47uF would be the next choice.
So far no more overheating. I also changed the pcb layout so that the caps are near the regulator as possible. This made me use surface mount caps (as Andy already suggested earlier
) and rotate the regulator 180 degrees. Also the solder pads for the power supply cables are arranged differently. So no major changes.
So, if any of you power supply wizards see any false magic being practised here please give me a shout
.
Need to order a few boards soon as I want to make another ECU for the FreeEMS and keep that in the car.
Re: VW Golf -89 Street/Trackday Car with ELMicro CardS12
Posted: Thu Jun 27, 2013 4:14 am
by TonyS
Hi MrOnion,
Do you have a list of specific manufacturer's (or distributor's) part numbers for the components you plan on using for the power supply circuitry? Thanks
Re: VW Golf -89 Street/Trackday Car with ELMicro CardS12
Posted: Thu Jun 27, 2013 6:46 pm
by MrOnion
Hi TonyS,
The regulators that I use are:
Micrel MIC29150-5.0BT
http://www.micrel.com/_PDF/mic29150.pdf
or
National LM2940CT-5
http://www.ti.com/lit/ds/symlink/lm2940-n.pdf
10/22uF Tantalum caps are from Vishay:
http://www.vishay.com/docs/40002/293d.pdf
Package is size E, 35V and ESR is about 0.6ohm.
100nF (0.1uF) Ceramics from Murata:
http://psearch.murata.com/capacitor/pro ... A01%23.pdf
Package is 1206, 25V, NP0.
I guess NP0 versions are better for this application than X7R:s?
The polyfuses RXE020/030 are from Tyco and the MOV is a S20K20 from Epcos.
Re: MrOnion's OnionBoard - GP IO/Power PCB (requires CPU boa
Posted: Mon Oct 07, 2013 10:16 pm
by MrOnion
Ok,
Did a final change to the vegetableboard and reorganized the solderpads so molex minifit connectors can be used if desired...
Few boards are now ordered so will see how they look when they arrive...
Re: MrOnion's OnionBoard - GP IO/Power PCB (requires CPU boa
Posted: Mon Oct 07, 2013 11:49 pm
by Fred
:-o oh oh oh!!! :-) :-D
Re: MrOnion's OnionBoard - GP IO/Power PCB (requires CPU boa
Posted: Tue Oct 08, 2013 3:56 am
by Dan
image link is broken :-S
Re: MrOnion's OnionBoard - GP IO/Power PCB (requires CPU boa
Posted: Tue Oct 08, 2013 8:50 am
by Fred
works4me
Re: MrOnion's OnionBoard - GP IO/Power PCB (requires CPU boa
Posted: Tue Oct 08, 2013 1:13 pm
by Dan
ok they are all working now? weird?