Data Sheet

1080
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181G–SAM-D21_Datasheet–09/2015
3. Respect the input common mode voltage through the following equations (where VCM_IN is the Input channel com-
mon mode voltage):
c. If |VIN| > VREF/4
z VCM_IN < 0.95*VDDANA + VREF/4 – 0.75V
z VCM_IN > VREF/4 -0.05*VDDANA -0.1V
d. If |VIN| < VREF/4
z VCM_IN < 1.2*VDDANA - 0.75V
z VCM_IN > 0.2*VDDANA - 0.1V
4. The ADC channels on pins PA08, PA09, PA10, PA11 are powered from the VDDIO power supply. The ADC perfor-
mance of these pins will not be the same as all the other ADC channels on pins powered from the VDDANA power
supply.
5. The gain accuracy represents the gain error expressed in percent. Gain accuracy (%) = (Gain Error in V x 100) /
(2*Vref/GAIN)
Table A-18. Single-Ended Mode (Device Variant A)
Symbol Parameter Conditions Min. Typ. Max. Units
ENOB Effective Number of Bits With gain compensation - 9.5 9.8 Bits
TUE Total Unadjusted Error 1x gain - 10.5 40.0 LSB
INL Integral Non-Linearity 1x gain 1.0 1.6 7.5 LSB
DNL Differential Non-Linearity 1x gain +/-0.5 +/-0.6 +/-0.95 LSB
Gain Error Ext. Ref. 1x -10.0 0.7 +10.0 mV
Gain Accuracy
(4)
Ext. Ref. 0.5x +/-0.1 +/-0.34 +/-0.4 %
Ext. Ref. 2x to 16X +/-0.01 +/-0.1 +/-0.15 %
Offset Error Ext. Ref. 1x -5.0 1.5 +10.0 mV
SFDR Spurious Free Dynamic Range
1x Gain
F
CLK_ADC
= 2.1MHz
F
IN
= 40kHz
A
IN
= 95%FSR
63.1 65.0 66.5 dB
SINAD Signal-to-Noise and Distortion 50.7 59.5 61.0 dB
SNR Signal-to-Noise Ratio 49.9 60.0 64.0 dB
THD Total Harmonic Distortion -65.4 -63.0 -62.1 dB
Noise RMS T = 25 C - 1.0 - mV