Atmel Xplained Pro Evaluation Kit ATSAMD20-XPRO ATSAMD20-XPRO Data Sheet

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Atmel | SMART SAM D20 [DATASHEET]

Atmel-42129K–SAM-D20_datasheet–06/2014

The AC contains a voltage doubler that can reduce the resistance of the analog multiplexors when the supply voltage is 
below 2.5V. The voltage doubler is normally switched on/off automatically based on the supply level. When enabling the 
comparators, additional start-up time is required for the voltage doubler to settle. If the supply voltage is guaranteed to be 
above 2.5V, the voltage doubler can be disabled by writing the Low-Power Mux bit in the Control A register 
(CTRLA.LPMUX) to one. Disabling the voltage doubler saves power and reduces the start-up time.

The V

DDANA

 scaler generates a reference voltage that is a fraction of the device’s supply voltage, with 64 levels. One 

independent voltage channel is dedicated for each comparator. The scaler is enabled when a comparator’s Negative 
Input Mux bit group in its Comparator Control register (COMPCTRLx.MUXNEG) is set to five and the comparator is 
enabled. The voltage of each channel is selected by the Value bit group in the Scaler x registers 
(SCALERx.VALUE[5:0]).

STATE0

STATE1

WSTATE[1:0]

INTERRUPTS

EVENTS

INPUT SIGNAL

UPPER LIMIT OF WINDOW

COMP0

COMP1

INTERRUPT

SENSITIVITY

CONTROL

&

WINDOW

FUNCTION

LOWER LIMIT OF WINDOW