MembersPage/KeithDurand (2005-08-06 07:59:11)

5-8-2005

Current plans are to get the Genboard 3.3 running, and then make a new board to match the CBR600 application. The goal is to fit it in a very small case, use SMT components almost everywhere.

Injectors are high Z, and this setup uses the stock Denso COP coils.

I would like to keep:

4 injector channels

4 ignition channels

2 VR channels

For other analog inputs, MAP, TPS, CTS and IAT will likely be all that remains. Maybe wideband 02 with permission.

Ultimately, I might steal the PWM output (OC0) to control an electric water pump, since the injectors don't need it.

Digikey has some nice parts for power switching:

IRGS14C4DL-- 430V clamping, logic level IGBT. D2pak.

IPS0315-- Smart FET, 12A, 50V clamp. Seems like it includes a driver, can I drop the 33151 and drive directly? (must be sure to change to non inverting) Also, is the flyback necessary? It claims that it can handle demag of "most" things.

The FETdriver and the flyback is necessary for PWM-ing, even if the smart FET has clamping. I don't recommend driving the FETs directly with the uC outputs. With highZ injectors or with ballast resistors in series with the lowZ injector it could work.

Q. Would DD flyback reduce noise on ground?

compared to what ? We separate GND5 from GND, so some GND5 noise isn't a big issue (also, unavoidable). The flyback protects the FETs: primarily from overvoltage, but also from heat (if the FETs have internal clamping).

VR sensor negative going (falling edge) zero crossing happens at the center of the tooth (or gap, depending the connected polarity).


4-8-2005

I got the VEMS wired and talking on the serial port. Seems like it had the bootloader installed already, but not the rest of the firmware. This took a while to figure out how to solve...

They are always shipped with a test firmware, that talks 9600,8N1. If you try in 19200 baudrate after bootup, you can only talk to the bootloader.