topic MC9S08RE16 stop3 current in 8-bit Microcontrollers

MC9S08RE16 stop3 current

stevec — Fri, 27 Jul 2007 16:27:48 GMT

I have an MC9S08RE16 set into stop3 mode and get a current of 1.2mA (down from 4.9mA running with 16MHz crystal). This is a rather more than I expected. Can someone give me some pointers as to how to reduce this.

Steve

Re: MC9S08RE16 stop3 current

tonyp — Fri, 27 Jul 2007 17:13:10 GMT

If you have any floating pins, tie them or pull them to either Vdd or Vss.

Is this pure STOP3 you're measuring? Or, do you periodically wake up to service some interrupt, possibly more often than you had expected?

Re: MC9S08RE16 stop3 current

stevec — Fri, 27 Jul 2007 21:12:49 GMT

I'm planning on pure stop3. Nothing to wake it up except the KBI function. I have put together a circuit with only the uP on it, all peripheral chips have been omitted. I have made all pins as o/ps before going into stop3 mode and this then gives me 0.9mA instead of 1.15mA stop3 current. 0.9mA if o/ps are set high or low.

Re: MC9S08RE16 stop3 current

Nik — Fri, 19 Sep 2008 05:28:06 GMT

Hi Steve,

You are having better luck than I am. When I enter STOP3, the XOSC continues to run.

I tried STOP2, the crystal stops, but it won't wake up. Well, the crstal does, but that's it. This is a MC9S08JM60.

Regards,

Robert