The N76E003 ADC can select an internal band-gap voltage as the input pin, which can be used to get the ADC reference voltage, for more accurate ADC results.
At room temperature, all N76E003 band-gap voltage values will be calibrated within the range of 1.17V to 1.27V. If you want to get the actual band-gap value for N76E003, read the 2 bytes value after the UID address.
There are 2 bytes after the UID address that store the actual band-gap value, but the actually valid bit is 12.
The first byte is the upper 8 bits, and the lower 4 bits of the second byte are the lower 4 bits of the 12 bit.
Reading and calculation steps:
Read a bad-gap value with IAP by reading UID;
Merge the upper 8 bits and the lower 4 bits;
Use the following formula to convert to an actual voltage value.
Formula:
Calculation example:
Read the 2 bytes value after the UID address, wherein the first byte value is 0x64, and the second byte value is 0x0E, merged as 0x64E = 1614. The conversion result is as follows: