ATtiny1624/1626/1627

ADC

Operating conditions:

T_A = [-40, 125]°C
Sample rate defined for SAMPDUR = 0x02 with ADC in Free-Running mode
Applies for all allowed combinations of VREF selections and sample rates, unless otherwise specified
Characteristics are identical with and without PGA enabled, unless otherwise specified

Table 1. Power Supply, Reference and Input Range
Symbol	Description	Conditions	Min.	Typ.	Max.	Unit
V_DD	Supply Voltage		1.8	-	5.5	V
V_REF	Reference voltage	REFSEL = Internal Reference	1.024	-	V_DD - 0.5
		REFSEL = External Reference	1	-	5.5
		REFSEL = V_DD	1.8	-	5.5
C_IN	Input capacitance	PGA disabled	-	8	-	pF
C_IN	Input capacitance	PGA enabled	-	7	-	pF
R_IN	Input resistance		-	10	-	kΩ
V_IN	Input voltage range	Single-ended mode	0	-	V_REF	V
V_IN	Input voltage range	Differential mode	-0.1	-	V_DD + 0.1	V

Table 2. Clock and Timing Characteristics
Symbol	Description	Conditions		Min.	Typ.	Max.	Unit
f_{CLK_ADC}	Conversion rate	PGA disabled	REFSEL = Internal Reference	-	-	187	ksps
			REFSEL = External Reference	-	-	375
			REFSEL = V_DD	-	-	375
		PGA enabled	REFSEL = Internal Reference	-	-	107
			REFSEL = External Reference	-	-	181
			REFSEL = V_DD	-	-	181
CLK_ADC	ADC clock frequency	REFSEL = Internal Reference		300	-	3000	kHz
		REFSEL = External Reference		300	-	6000
		REFSEL = V_DD		300	-	6000
T_S	Sampling time	PGA disabled		0.5	-	255.5	CLK_ADC cycles
T_S	Sampling time	PGA enabled		1	-	256	CLK_ADC cycles

Table 3. Accuracy Characteristics External Reference⁽¹⁾
Symbol	Description	Conditions	Min.	Typ.	Max.	Unit
Res	Resolution		-	-	12	bit
E_INL	Integral nonlinearity	V_DD = 3.0V V_REF = 2.048V CLK_ADC = 2.5 MHz Differential mode	-2.0	0.8	2.0	LSb
E_DNL	Differential nonlinearity		-0.9	0.8	1.4
E_OFF	Offset error		-28	1.5	28
E_GAIN	Gain error		-2.1	0.6	2.1
E_T	Total unadjusted error		-	5	21

Note:

1.These values are based on characterization and are not covered by production test limits.

Table 4. Accuracy Characteristics Internal Reference⁽¹⁾
Symbol	Description	Conditions	Min.	Typ.	Max.	Unit
Res	Resolution		-	-	12	bit
E_INL	Integral nonlinearity	V_DD = 3.0V V_REF = 2.048V CLK_ADC = 2.5 MHz Differential mode	-2.3	1	2.3	LSb
E_DNL	Differential nonlinearity		-0.9	1	1.6
E_OFF	Offset error		-28	1.5	28
E_GAIN	Gain error		-81	7	81
E_T	Total unadjusted error		-	10	42

Note:

1.These values are based on characterization and are not covered by production test limits.

Table 5. Accuracy Characteristics with PGA Enabled⁽¹⁾
Symbol	Description	Conditions	Min.	Typ.	Max.	Unit
N_RMS	Input Noise	PGA Gain = 1V/V	-	32	-	µV_RMS
		PGA Gain = 2V/V	-	63	-
		PGA Gain = 4V/V	-	125	-
		PGA Gain = 8V/V	-	250	-
		PGA Gain = 16V/V	-	500	-
E_GAIN	Gain error V_DD = 3.0V	PGA Gain = 1V/V	-0.4	-0.2	0.4	%
		PGA Gain = 2V/V	-0.5	-0.2	0.5
		PGA Gain = 4V/V	-0.7	-0.3	0.7
		PGA Gain = 8V/V	-1.2	-0.6	1.2
		PGA Gain = 16V/V	-1.7	-0.8	1.7

Note:

1.These values are based on characterization and are not covered by production test limits.