LPC845M301JHI33 ADC is Not Working

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LPC845M301JHI33 ADC is Not Working

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srchethan
Contributor I

Will you please help?

I am using LPC845 33 pin chip. Properly connected VREFP and VREFN
I am giving an input of 1.7V to PIO0_21(ADC_5), pin 28

When tried to initialise the ADC, first ensuring IOCON PIO0_21 is set for no-pull-up and no-pull-down
and then assigning ADC_5 through SWM, the voltage goes to 0.3V

Even if I proceed to calibrate and read, I get a low value of 0x19

I tried changing the sequence of initializing SWM and then IOCON, and this time
first I get some 1.7V but the moment the IOCON is loaded, the voltage drops.


To avoid any problem related to library, I even tried using all register addresses and bit values directly

No change in the result.

I had tried SDK 2.5 and 2.8 versions both. I need some help very much, please.

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Alice_Yang
NXP TechSupport
NXP TechSupport

Hello srchethan,

About configure ADC pins and other configurations related ADC, please first 

have a look at the ADC demo under SDK, use the latest version.

 

3333.jpg

 

Regards,

Alice

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