Voltlog  

But how can the device start sucking water/moisture if it's hermetically sealed?

@@voltlog I assume that it is sealed when it leaves the factory. But after some years the seal and the connectors are becomming vulnerable.

It's called as DAE or PCE Pressure control element. It doesn't allow air inside but it can release air from inside

you prolly dont care but if you're stoned like me during the covid times you can stream pretty much all of the new series on InstaFlixxer. I've been streaming with my brother these days =)

@Kase Mekhi Yup, been using Instaflixxer for since december myself =)

How can it measure pressure if it's a sealed unit?

​@@JamieVegasits not sealed, the black thing on top is vent

@@Skaude It's sealed, and the black thing is just a rubber flexible stopper, it allows atmospheric pressure to be detected by the unit on the board, without actual contact with air.

@@JamieVegas its a Gore Vent

I have worked with a lot of ECUs from Bosch and Continental. None of them had an internal pressure sensor but each had such a vent plug.

This could be true if the ECU indeed contains the pressure sensor but I haven't confirmed that yet.

Good catch, thanks!

@@voltlog Also the extra pads after each IC on the bottom tells you the direction of the wave soldering. They are "solder thieves" and are there to prevent the last pins from being bridged.

This one was pretty cheap at $10 shipped. I am assuming it was functional.

yup I would imagine Bosch would spin this design around for multiple types of vehicles.

I saw the filtering passives on the pcb right next to connector pins but you are saying this connector also has built-in chokes and capacitors? Then it would make an interesting teardown, maybe in a future video.

@@voltlog Generally a lot of them do, often only on particular pins, with the extra components on the board being there for clamping purposes. Depends on the model though, if they have run out of board space then the connector becomes the filter space, or if they have need for extra filtering during EMI testing. Just pop off the steel shield and see if there is ceramic plating or ferrite plates inside. They typically are pressed over the pins before the bend, snug up against the back of the connector, with a grounding ring on the outside for the capacitor type.

It's about ASIL levels. Some Cypress products are ISO 26262 conpliant too. 😉

Back in 2012 I worked on a project where Bosch, CRF and Freescale designed a new ECU controller chip and safety certifications were a big thing. Regarding on how the agreement was made between the partners this new architecture was going to be sold by each partner to a different market with slight variations.

Infineon now is the biggest player,it just bought cypress,it was the second largest manufacturer of automotive semiconductors slighty behind NXP,now it is way ahead.

kordta makes sense 👍🏼

From the part number it was most likely made by Aktiv-Electronic, Berlin

@@megatesla Thanks for the info!

Is it possible to replace it with a different one cause I can't find anything with this AE number ?

thanks!

Good catch, thanks!

I think the vias at the edges are as much if not more for heat transfer between the layers than for EMI protection.

standard EMC management, heat transfers are the pafs an through holes of the pads under the driver chips

Thanks for the info.

Design must survive reverse polarity WITHOUT damage. NO BLOWING FUSES!

ECU must survive reversed supply without damage. NO BLOWN FUSES allowed.

Depending on requirements that diode is added for the exact purpose of blowing the fuse ,that does not mean that other protection is not pressent for the ecu to survive the reverse polarity.

@@Brandon-wo2xj have been designing such ECU and am quite familiar with the specifications by the Auto manfsvturers. Blowing fuses is NOT allowed

I haven't checked but it could also be in series, preventing reverse polarity without any damage.

15

I think the problem would be the development tools for that processor, compiler/IDE. Other than that it's a nice idea, this would be a great general purpose Digital/Analog control box.

Yup I think you are right!

Most likely the CAN transceiver is the 8 pin IC (??43547) between the large Infineon controller and the TDK common mode filter (ZJY5-2). At least the pin-out looks correct. And you are right, there is no conformal coating. It seems to be common practice not to apply conformal coating on these PCBs. Since the ECU is sealed, residual solvents in the lacquer can not evaporate and electrolytic processes can dissolve parts of the solder which then can cause short circuits between IC pins.

In general conformal coatings can create their own problems. Not in favour at all also costly messy manfacturing step

I was actually wondering why they didn't use conformal coating, but this certainly answers my question, makes sense now as that would possibly be unreliable long term.

My guess is the module is sealed, thus no need for conformal coating.

why?

Not really, at least you know they will not fail for at least 20 years if properly specified and used correctly, while electolytics all are guaranteed to fail after some time. Tantalum if used well derated and current limited is not going to go bang, especially for quality manufacturers who run them conservatively.