How To Read The A/D Converter Characteristics Table; Figure 15-14: Overall Error - NEC V850E/CA2 JUPITER Preliminary User's Manual

15.7 How to read the A/D Converter Characteristics Table

Here, special terms unique to the A/D converter are explained.
(1) Resolution
This is the minimum analog input voltage that can be identified. That is, the percentage of the ana-
log input voltage per bit of digital output is called 1LSB (Least Significant Bit). The percentage of
1LSB with respect to the full scale is expressed by %FSR (Full Scale Range).
When the resolution is 10 bits,
10
1LSB = 1/2 = 1/1024 = 0.098%FSR
Accuracy has no relation to resolution, but is determined by the overall error.
(2) Overall Error
This shows the maximum error value between the actual measured value and the theoretical
value. Zero scale error, full scale error, non-linearity error and errors which are combinations of
these express the overall error.
Note that the quantization error is not included in the overall error in the characteristics table.
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Chapter 15 A/D Converter

Figure 15-14: Overall Error

1.......1
Ideal line
0.......0
0
Analog input
Preliminary User's Manual U15839EE1V0UM00
Overall
error
AV
REF