EFM32WG880 Datasheet, PDF (38/85 Pages) Silicon Laboratories – Operation from backup battery when main power drains out

...the world's most energy friendly microcontrollers
3.10.1 Typical performance
Figure 3.26. ADC Frequency Spectrum, Vdd = 3V, Temp = 25°C
1.25V Reference
2.5V Reference
2XVDDVSS Reference
5VDIFF Reference
VDD Reference
2014-06-13 - EFM32WG880FXX - d0197_Rev1.40
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