LPC8xx measure bandgap with ADC?

phatpaul — Thu, 29 Sep 2022 15:54:02 GMT

Apparently, the LPC845 has a 0.9V bandgap reference, mentioned in the Analog Comparator section of the manual. Is it possible to measure that 0.9V with the ADC? I don't see an option for routing it to an ADC input channel.

I want to be able to measure VCC and apply corrections to ADC measurements (of absolute value, not ratiometric to VCC). I also want to compensate the DAC output value based on VCC value.

I'm coming from the Kinetis KL0x which has this ability.

Re: LPC8xx measure bandgap with ADC?

RaRo — Fri, 07 Oct 2022 20:01:09 GMT

Hi @phatpaul,

You are right, there is not an option for routing the 0.9V bandgap reference to an ADC input channel.

Additionally, you could check this information that could help with your design:

AN5250. How to Increase the Analog-to-Digital Converter Accuracy in an Application
AN4373. Cookbook for SAR ADC Measurements

Regards, Raul.

LPC MicrocontrollersのトピックLPC8xx measure bandgap with ADC?

LPC8xx measure bandgap with ADC?

Re: LPC8xx measure bandgap with ADC?