ATMEGA128-16AU SL383 Atmel, ATMEGA128-16AU SL383 Datasheet - Page 239

• Manufacturer Part Number: ATMEGA128-16AU SL383
• Manufacturer: Atmel

ADC Accuracy
Definitions
2467S–AVR–07/09
An n-bit single-ended ADC converts a voltage linearly between GND and V
(LSBs). The lowest code is read as 0, and the highest code is read as 2
Several parameters describe the deviation from the ideal behavior:
•
Figure 115. Offset Error
•
Figure 116. Gain Error
•
Offset: The deviation of the first transition (0x000 to 0x001) compared to the ideal transition
(at 0.5 LSB). Ideal value: 0 LSB.
Gain Error: After adjusting for offset, the gain error is found as the deviation of the last
transition (0x3FE to 0x3FF) compared to the ideal transition (at 1.5 LSB below maximum).
Ideal value: 0 LSB
Integral Non-linearity (INL): After adjusting for offset and gain error, the INL is the maximum
deviation of an actual transition compared to an ideal transition for any code. Ideal value: 0
LSB.
Output Code
Output Code
Offset
Error
Gain
Error
V
V
REF
REF
Input Voltage
Input Voltage
Ideal ADC
Actual ADC
n
Ideal ADC
Actual ADC
-1.
ATmega128
REF
in 2
n
steps
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