lpc54628 adc value decaying issue

kuanweichi — Fri, 21 Dec 2018 08:30:00 GMT

I follow up the fsl driver to initialize lpc54628 adc. My vcc is 3.3 and vref is also 3.3. While I sampled a 1.8V, I got a 0x8B0 at first time. However, the second time I sampled, I've got a 0x892, and the third time 0x888, and so on decaying until zero.

I don't know what's going on.

But I find out that the phenomenon is resetable by POWER_EnablePD(kPDRUNCFG_PD_ADC0); and POWER_DisablePD(kPDRUNCFG_PD_ADC0);

Is any configuration I forgot?

I've try burst, single step, any config ,and the decaying still happened.

topic lpc54628 adc value decaying issue in LPC Microcontrollers

lpc54628 adc value decaying issue