ATMEGA169 ATMEL [ATMEL Corporation], ATMEGA169 Datasheet - Page 202

• Manufacturer Part Number: ATMEGA169
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

ADC Accuracy Definitions
202
ATmega169/V
An n-bit single-ended ADC converts a voltage linearly between GND and V
steps (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 92. Offset Error
•
Figure 93. 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
Ideal ADC
Actual ADC
2514P–AVR–07/06
n
-1.
REF
in 2
n