Alessandro Strazzero

MC9S12 noise immunity

Discussion created by Alessandro Strazzero on Oct 9, 2007
Latest reply on Oct 9, 2007 by Alban Rampon
Dear everybody,
in the recent past we have manufactured with success boards targeted to control
motorbikes engines using the MC68HC711E9 microntroller.
Now we have replaced the MC68HC711 part with the MC9S12C32MFA25 part in order to
enhance the features of our boards. With great surprise we are detecting some problems
caused by noise released from an inductor coil used to make the spark.
The PCB layout and the components around the microcontroller are the same as our
previous boards. So we suspect that the MC9S12 part has not the same noise immunity
of the MC68HC11 part.

Do you experience our same problems in your applications ? Are we using a not suitable
microcontroller for our application ? How could Freescale help us to workaround these
noise problems ?
Any advice will be very appreciated.
Best Regards