rusefi.com

Any advice? May be we can megre to rusEFI? Uses a Bosch LSU 4.2 sensor.
I found that open project - Waltech WBO2


heater control mosfet: IRL3803


Downlad source code (zip file)
Schematic: image
Gerber files (zip file)
Parts list/BOM
Kicad project (zip file)

Hookup and operation manual
Design manual

This looks pretty cool! I will check the source code a bit later to figure out how complex it would be to make our own WB controller module out of it.

Karl from waltech.com has donated the controller design - we are allowed to change it

The Waltech Waltech WBO2 Is yours to do whatever you like with.

I have checked-in the KiCad stuff into our repository

What is even cooler is that Karl has shared a draft of his article about all this - https://docs.google.com/document/d/1IOJQUfc44lbZ_TbdSRzF9B-w5-jzqlUJglZnK6uHu5w

Document very interesting.

Yes Karl is cool. He's basically made a circuit that's almost the same as the BOSH chip and he's done a good job documenting it. However much easier to get the parts for Karls circuit. Last I recall his code would decode the WO2 and and generate a NO2 signal. It should be fairly easy to make into a different module.

Oh, also keep an eye on licence, so don't blind copy. Karl seems cool about it, however there are others that will blow a gasket.

Hmmm....

Wonder if I could include this into the MAP board for my motorcycle? I know LOTS of people that would like O2 feedback control.
That would mean I'd be modulating the MAP sensors to control AFR though, so might need to bump the MCU from MSP430 to ARM M4...
... need engine speed input too.

The Waltech Waltech WBO2 Is yours to do whatever you like with.
...
I'll put the MIT license on the WBO2 page.
...
Sincerely,
--Karl

I will start by using the Waltech board as is to implement the logic and later we will embed it into Frankenso I guess.

IRL3803 mosfet - heater control - is it going to be happy with me driving it by 3.3v?

pump driver - same question. Would it work with 3.3v or do I need to apply a 5v via a TC4427?

For IRL3803 the Vgs is 1.0V, so you should be fine with 3.3V drive.

The TC4427 is the same chip we use for the IGN driver. So we are fine with MCU drive. However I don't know if 3.3V will be enough voltage for the output. I say try it and see what happens. If you end up with 100% duty cycle, then it needs 5V. Also remember the output can be separate from the drive. If you populate U2 and connect to 12V battery, you'll have 5V on your output, but you can drive with 3.3V.

kb1gtt wrote:The TC4427 is the same chip we use for the IGN driver.

external TC4427 was my plan for pump driver - the original board does not have TC4427, just that op-amp magic for pump driver which I do not get completely. Does it mean pump is not consuming much current?

That pump thing is a special thing. I think it's an AN signal, but it might have some PWM going on. I'd use the original op-amp as it has know gain, offset, ect.

Not much silkscreen on this board

Totally different option: CJ125 chip from Bosch

http://www.bosch-semiconductors.de/media/pdf_1/einzeldownloads/engine_management/CJ125_Product_Info.pdf

Seems to be available from China:


Pretty much self contained, how comes we did not consider it yet?

Some where around here we have considered it. I think it was kind of done here http://rusefi.com/forum/viewtopic.php?f=5&t=209&p=288 but is not very clear.

For $59 you can buy pre-assembled boards that use the CJ125 at it's core from here http://www.ecotrons.com/products/wideband_controller_alm-board/

http://www.wide-band.com/product-p/apsx_d1diy.htm
< $30 USD; works with LSU4.2