LPC8xx measure bandgap with ADC?

[phatpaul]

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.

[RaRo]

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.