D12320VF25IV Datasheet, PDF (751/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 16 A/D Converter (8 Analog Input Channel Version)
frequently, as in scan mode, if the current charged and discharged by the capacitance of the
sample-and-hold circuit in the A/D converter exceeds the current input via the input impedance
(R_in), an error will arise in the analog input pin voltage. Careful consideration is therefore required
when deciding the circuit constants.
*¹
*¹
R_in* ²
100 Ω
0.1 μF
Notes: Values are reference values.
1.
10 μF
0.01 μF
AV_CC
V_ref
AN0 to AN7
AV_SS
2. R_in: Input impedance
Figure 16.7 Example of Analog Input Protection Circuit
A/D Conversion Precision Definitions: The chip’s A/D conversion precision definitions are
given below.
• Resolution
The number of A/D converter digital output codes
• Offset error
The deviation of the analog input voltage value from the ideal A/D conversion characteristic
when the digital output changes from the minimum voltage value B'0000000000 to
B'0000000001. (See figure 16.9.)
Rev.6.00 Sep. 27, 2007 Page 719 of 1268
REJ09B0220-0600