upd70f3017ay Renesas Electronics Corporation., upd70f3017ay Datasheet - Page 326

• Manufacturer Part Number: upd70f3017ay
• Description: V850/sa1tm 32-/16-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

11.6 How to Read A/D Converter Characteristics Table
Here, special terms unique to the A/D converter are explained.
326
(1) Resolution
(2) Overall error
This is the minimum analog input voltage that can be identified. That is, the percentage of the analog 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). %FSR indicates the ratio of analog input voltage that
can be converted as a percentage, and is always represented by the following formula regardless of the
resolution.
1LSB is as follows when the resolution is 10 bits.
1LSB = 1/2
Accuracy has no relation to resolution, but is determined by overall error.
This shows the maximum error value between the actual measured value and the theoretical value.
Zero-scale error, full-scale error, linearity error and errors that are combinations of these express the overall
error.
Note that the quantization error is not included in the overall error in the characteristics table.
1%FSR = (Max. value of analog input voltage that can be converted − Min. value of analog input voltage that
= 0.098%FSR
= (AV
= AV
10
can be converted)/100
= 1/1024
REF
REF
/100
– 0)/100
1 …… 1
0 …… 0
CHAPTER 11 A/D CONVERTER
Figure 11-9. Overall Error
0
User’s Manual U12768EJ4V1UD
Ideal line
Analog input
Overall
error
AV
REF