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ACHIEVING HIGH ACCURACY AND 13-BIT RESOLUTION WITH ST7LITE2 ADC

4.1 SOFTWARE FLOW

In software, firstly the AMPCAL and AMPSEL bits are set. Then the ADC is sampled for a de-

fined number of times and averaged. This output is then stored in EEPROM as an offset. This

is then used in a program to get precise ADC output by subtracting it from subsequent ADC

samples (Refer to Figure 7).

A total of 100 readings are taken and stored in EEPROM for the same analog input. And each

reading has a result of 25 averaged samples + offset compensation. These are to allow you to

compare it directly with respect to analog input.

However, the samples to be taken depend on the application so it is user-configurable. This

can be changed by using the “no_of_sample” value in software.