Disable sleep clock WP7702

[FransKanters]

Hi all,

I’m measuring a small noise signal radiating from the Mangoh red with a WP7702 module in the range of 64KHz. Since we are using this module in a project where we need a very sensitive 55KHz receiver, this signal is disturbing our signal. I suspect it may be a second harmonic of the 32.768KHz sleep clock.

Is there a way to disable the 32KHz sleep clock? That would make it easy to solve or rule it out.

Best regards,
Frans.

[jyijyi]

here says:

pin 23 generates a 32KHz square wave while the unit is powered, it is available as long as the unit is in ULPM (so effectively off)

How to generate 32KHz sleep clock

@markfisher So pin 23 generates a 32KHz square wave while the unit is powered, it is available as long as the unit is in ULPM (so effectively off). So if you are using the unit in sleep mode (at+ksleep) it will still be there, the USB_SS is not really a ‘mode’ of the unit as this just applies to the USB bus, not the unit as a whole. If you don’t have USB connected (like I have tested it with) then USB is not part of the discussion. Does that answer the question? Regards Matt

BTW, do you see this 32K clock when module is in active mode?

[FransKanters]

Hi,

Yes, I can measure the 32KHz in normal operation mode.

Best regards,
Frans.

[jyijyi]

Then it seems you cannot stop it