32.768khz crystal current CC1110

ronnym said:

What is the current drain for the 32KHz crystal oscillator in PM2 mode?

The CC1110F32 datasheet indicates the current consumption for the device in PM2 is 0.5uA.  This is indicated in Table 6.

I did read table 6. It states that the current is measured with the LP RCOSC active. Wouldn't the current drain rise if using the 32.768 kHz crystal oscillator instead? One post had mentioned it as being as much as 30 uA. I hope this is not the case...

Good point.  I missed the comment on the LP RCOSC.

So is there any data out there for the current drain in PM2 while using the LPXOSC @ 32.768kHz?

Thanks again,

Ron

Thanks for the follow up and running some quick experiments on the bench.

In comparison, some external 32.768KHz crystal oscillators that I had found consumed 1.2mA on the supply.

BrandonAzbell said:

Thanks for the follow up and running some quick experiments on the bench.

In comparison, some external 32.768KHz crystal oscillators that I had found consumed 1.2mA on the supply.

I bet that is a TCXO oscillator...  I am amazed by the lowly Timex type wrist watch that keeps accurate time to 20 seconds a year on a tiny 1.5 volt cell.

How did you get the chip to drain only 1.1 microamps ? I am running it on Power Mode 3 and cannot get under 80 microamps !

This was a while ago, mind you... But, the current drain value I got was only 1.1uA above the drain when using the internal RC oscillator. 1.1uA total drain would be awesomeness itself! It does sound like your drain in PM3 is high though.

Ron