EFM32WG232 Datasheet, PDF (38/75 Pages) List of Unclassifed Manufacturers – The EFM32 MCUs are the world’s most energy friendly microcontrollers.

...the world's most energy friendly microcontrollers
Figure 3.27. ADC Integral Linearity Error vs Code, Vdd = 3V, Temp = 25°C
1.25V Reference
2.5V Reference
2XVDDVSS Reference
5VDIFF Reference
VDD Reference
2014-06-13 - EFM32WG232FXX - d0186_Rev1.40
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