MB91360G_05 Datasheet, PDF (225/239 Pages) Fujitsu Component Limited. – 32-bit RISC Microcontroller

MB91360G Series
7. A/D Converter Glossary
• Resolution
The smallest change in analog voltage detected by A/D converter.
• Linearity error
A deviation of actual conversion characteristic from a line connecting the zero-traction point (between “00 0000
0000” ↔ “00 0000 0001”) to the full-scale transition point (between “11 1111 1110” ↔ “11 1111 1111”) .
• Differential linearity error
A deviation of a step voltage for changing the LSB of output code from ideal input voltage.
• Total error
A difference between actual value and theoretical value. The overall error includes zero-transition error, full-
scale transition error and linearity error.
Total error
3FFH
3FE_H
3FD_H
Actual conversion
characteristic
{1 LSB' × (N − 1) + 0.5 LSB'}
1.5 LSB'
004_H
003H
002_H
001H
VNT
(measured value)
Actual conversion
Ideal characteristic
0.5 LSB'
AVRL
Analog input
AVRH
Total error of digital output N
=
VNT − {1 LSB’ × (N − 1)
1 LSB’
+ 0.5 LSB’}
[LSB]
VOT’ (Ideal value) = AVRL + 0.5 LSB’ [V]
VFST’ (Ideal value) = AVRH − 1.5 LSB’ [V]
VNT : A voltage for causing transition of digital output from (N − 1) to N
(Continued)
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