p*(LPC932 current draw

[Alan Oxenbould]

Colleagues,
I am trying to determine the current consumption of P89LPC932:
- using medium external crystal oscillator (3.579 MHz)
- NO analogue functions
- NO watch-dog, NO RTC, NO brown-out

In addition, I need to measure the "power_down" current:
- whilst clock stopped, waiting for a Keyboard LEVEL interrupt-wake-up.

Any rough current measurements/estimates you could provide would be very much appreciated.

[Bauke Siderius]

Hi,

Roughly 1mA per MHz typical while running, you can divide this down with DIVM where you application code does not need the horsepower.
With a DIVM of 0xFF the part draws about the base current for the crystal oscillator drive circuit, medium crystal selection is about 500 uA.

Total power down is typically 0.1 uA.
To get the low power in total power down mode, turn off the WD run bit, and turn off the CLKLP in the AUXR register. And make sure no current is sourced through the pins of the part.

Regards,

Bauke