
175
8008H–AVR–04/11
ATtiny48/88
Differential Non-linearity (DNL): The maximum deviation of the actual code width (the interval
between two adjacent transitions) from the ideal code width (1 LSB). Ideal value: 0 LSB.
Figure 17-13. Differential Non-linearity (DNL)
Quantization Error: Due to the quantization of the input voltage into a finite number of codes,
a range of input voltages (1 LSB wide) will code to the same value. Always ±0.5 LSB.
Absolute accuracy: The maximum deviation of an actual (unadjusted) transition compared to
an ideal transition for any code. This is the compound effect of offset, gain error, differential
error, non-linearity, and quantization error. Ideal value: ±0.5 LSB.
17.11 ADC Conversion Result
After the conversion is complete (ADIF is high), the conversion result can be found in the ADC
Result Registers (ADCL, ADCH).
For single ended conversion, the result is
where V
IN is the voltage on the selected input pin and VREF the selected voltage reference (see
0x3FF represents the selected reference voltage minus one LSB.
17.12 Temperature Measurement
The temperature measurement is based on an on-chip temperature sensor that is coupled to a
single-ended ADC8 channel. Selecting the ADC8 channel by writing the MUX[3:0] bits in
Output Code
0x3FF
0x000
0
VREF Input Voltage
DNL
1 LSB
ADC
VIN 1024
VREF
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=