SH7014 Datasheet, PDF (451/754 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

14. Mid-Speed A/D Converter ⎯ SH7016, SH7017 ⎯
14.7 Usage Notes
The following points should be noted when using the mid-speed A/D converter.
14.7.1 Analog Voltage Settings
(1) Analog input voltage range
The voltage applied to analog input pins during A/D conversion should be in the range AV_SS ≤
ANn ≤ AV_CC (n = 0 to 7).
(2) AV_CC and AV_SS input voltages
For the AV_CC and AV_SS input voltages, set AV_CC = V_CC = 5V ±10% and AV_SS = V_SS. When the
mid-speed A/D converter is not used, set AV_CC = V_CC and AV_SS = V_SS.
14.7.2 Handling of Analog Input Pins
To prevent damage from surges and other abnormal voltages at the analog input pins (AN0 to
AN7), connect a protection circuit such as that shown in figure 14.8. This circuit also includes a
CR filter function that suppresses error due to noise. The circuit shown here is only a design
example; circuit constants must be decided on the basis of the actual operating conditions.
Figure 14.9 shows an equivalent circuit for the analog input pins, and table 14.6 summarizes the
analog input pin specifications.
AV_CC
100 Ω
AN0 to AN7
*
SH7016
0.1 μF
SH7017
AV_SS
Note: *
10 μF
0.01 μF
Figure 14.8 Example of Analog Input Pin Protection Circuit
Rev.5.00 Sep. 27, 2007 Page 417 of 716
REJ09B0398-0500