Delco 808 ecu info needed

[Ludis Langens]

Steve Sassine <n9480320 at garbo.nepean.uws.EDU.AU> wrote:
>    I am in need of some information on the identification of the IC's used
> in a declo ecu with the service No. 1227808. This ecu is used on a
> australian holden commodore 3.8l V6. Below shows the info I have collected
> so far.
> 
>     ECU has 65 pin memcal connector.

You mean 66 pins?  (Actually, I've seen some with one pin missing,
presumably as a key; so with only 65 pins.)

>  U8            1606958/MR8749                 CPU ???

GM custom MPU.  It contains RAM, SCI & SPI ports, 11 I/O bits, COP
watchdog, and a periodic interrupt timer.  I think you dropped a digit
from the part number.  I've seen four different numbers used: 16034980,
16069564, 16079434, 16139860.  The '34980 contains 512 bytes of SRAM,
the '139860 might have a full 1K.

>  U9             45148                         Delco IC

GM custom timer chip, something like the TPU in a 68332.

>  U10            34988                  Has ouput of MAP sensor connected
>                                        to pin 18 via 18K resistor.

Analog to Digital chip.  Interfaced via the SPI port.  This is a
standard NatSemi, TI, etc. part.

>  U11            54995                       Delco IC

GM custom limp home fuel controller chip.  Could also be a 16034986.

>  U4             034987/AD87465            connects to MAT sensor

O2 sensor amplifier.  This is a standard NatSemi part.

>  U5             44188                         ????

?????  Only the 1227165/1227808 style ECMs have this chip.  The other
P4's don't.

>  U2             missing

This would be a 16034985 or 16064606.  Current theory is that this
interfaces the MPU's TxD and RxD lines to the ALDL signal.

>  U7, U13, U3, U6, and U1 are mounted onto heat sink.

U7       GM custom IAC driver.
U13      Off the shelf high side driver (for fuel pump relay).  NatSemi
         has something like this.  Siemens has a device that is even a
         better match.
U3 & U6  Quad drivers.  These might be GM custom because I haven't
         found any standard parts with this pinout.
U1       Power supply - this might be GM custom too.


You forgot about U12.  It is a 16034984, 16052444, or 16079435.  It has
an SPI I/O port, the EST interface circuit, the Peak+Hold injector
driver controller, and some random signal buffers.

>            If any one can help me or can tell me where I can obtain data
> sheets on these IC's please rely to me on the email address below

NatSemi and TI have data available on the net (for the industry standard parts.)

>    Also I found,on this ecu, that the bolts that earth out the heat
> sink are not doing there job properly, ie. the heat sink was not earthed.
> Any ideas on what will happen in this case ?? will the ecu still work ??

GM doesn't appear to rely on the heat sink being grounded (earthed?). 
Witness the insulator on some of the components.


You might want to look at the schematics of the 1227748 ECM which I just
put online at: http://www.cruzers.com/~ludis/schematics

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/