SH7014 Datasheet, PDF (429/754 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

13. High Speed A/D Converter ⎯ SH7014 ⎯
13.6.6 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 13.12. 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 13.13 shows an equivalent circuit for the analog input pins, and table 13.10 summarizes the
analog input pin specifications.
100Ω
AVcc
AN0 to AN7
SH7014
*
0.1 μF
AVss
Note: *
10 μF
0.01 μF
Figure 13.12 Example of Analog Input Pin Protection Circuit
AN0 to AN7
1.0 kΩ
20 pF
1 MΩ
Analog multiplexer
Note: Numeric values are reference values.
High speed
A/D converter
Figure 13.13 Analog Input Pin Equivalent Circuit
Rev.5.00 Sep. 27, 2007 Page 395 of 716
REJ09B0398-0500