35.16 AC

Table 35-21. Analog Comparator Specifications
Operating conditions: V_DD = 3.0V T_A = 25°C
Symbol	Description	Min.	Typ.✝	Max.	Unit	Conditions
V_IN^*	Input voltage range	-0.2	—	V_DD	V
I_L	Input leakage current	—	5	—	nA
V_OFF^*	Input offset voltage	-30	±10	30	mV	0.1V < V_IN < (V_DD - 0.1V) CTRLA.HYSMODE = `0x0`
CMRR	Common Mode Rejection Ratio	—	60	—	dB	V_CM = V_DD / 2
V_HYST	Hysteresis	—	5	—	mV	CTRLA.HYSMODE = `0x1`
		—	10	—		CTRLA.HYSMODE = `0x2`
		—	15	—		CTRLA.HYSMODE = `0x3`
t_RESP	Response time, rising edge	—	180	—	ns	V_CM = V_DD / 2
t_RESP	Response time, falling edge	—	240	—	ns	V_CM = V_DD / 2
t_START	AC Start-up time	—	10	—	us	OSC32K enabled and running
✝ Data in the “Typ.” column is measured at T_A = 25°C and V_DD = 3.0V unless otherwise specified. These parameters are for design guidance only and are not tested. * These parameters are characterized but not tested in production.

Table 35-22. REFSCALE Specifications
Symbol	Description	Min.	Typ.✝	Max.	Unit	Conditions
V_REFSCALE	Reference Scaler Max Voltage	—	V_REF - REFSCALE_LSB	—	V	REFSCALE = `0xFF`
REFSCALE_RNG	Reference Scaler Range	0	—	V_REFSCALE	V
REFSCALE_LSB	Reference Scaler Resolution	—	1/ (256*V_REF)	—	V
E_REFSCALE⁽¹⁾	Reference Scaling Error	-2	—	+2	%	Excluding error from V_REF
t_READY^*	Ready Time	—	—	100	μs
✝ Data in the “Typ.” column is measured at T_A = 25°C and V_DD = 3.0V unless otherwise specified. These parameters are for design guidance only and are not tested. * These parameters are characterized but not tested in production. Note: Error given as a percentage of the selected REFSCALE reference voltage. Calculate the total accuracy of the comparator trip point when using a scaled reference voltage as follows: Error_Min(negative) = VREF_Min * (1 + 0.01E_{REFSCALE_}_Min) - VREF_Typ - \| VOFF \| Error_Max (positive) = VREF_Max (1 + 0.01*E_{REFSCALE_}_Max) - VREF_Typ + \| VOFF \| VREF_Min and VREF_Max represent the minimum and maximum values of the reference voltage. If V_REF is obtained from the device's internal V_REF source, refer to the VREF section to calculate the minimum and maximum V_REF values. If V_REF is obtained externally, the characteristics of the external V_REF source must be used to determine the minimum and maximum V_REF values. When input hysteresis is enabled, add ±V_HYST/2 to the rising and falling trip point.