259
8025I–AVR–02/09
ATmega48P/88P/168P/328P
Figure 21-10. Offset Error
• 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
Figure 21-11. Gain Error
• 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
V
REF
Input Voltage
Ideal ADC
Actual ADC
Offset
Error
Output Code
V
REF
Input Voltage
Ideal ADC
Actual ADC
Gain
Error