ATMEGA644PV ATMEL [ATMEL Corporation], ATMEGA644PV Datasheet - Page 249

• Manufacturer Part Number: ATMEGA644PV
• Description: 8-bit Microcontroller with 16/32/64K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

21.7.4
8011D–AVR–02/07
ADC Accuracy Definitions
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:
• Offset: The deviation of the first transition (0x000 to 0x001) compared to the ideal transition (at
Figure 21-10. Offset Error
• Gain Error: After adjusting for offset, the Gain Error is found as the deviation of the last
Figure 21-11. Gain Error
• Integral Non-linearity (INL): After adjusting for offset and gain error, the INL is the maximum
0.5 LSB). Ideal value: 0 LSB.
transition (0x3FE to 0x3FF) compared to the ideal transition (at 1.5 LSB below maximum).
Ideal value: 0 LSB
deviation of an actual transition compared to an ideal transition for any code. Ideal value: 0
LSB.
Output Code
Output Code
Offset
Error
ATmega164P/324P/644P
Gain
Error
V
V
REF
REF
Input Voltage
Input Voltage
n
Ideal ADC
Actual ADC
Ideal ADC
Actual ADC
-1.
REF
in 2
n
steps
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