SH7763 Datasheet, PDF (1737/2026 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC Engine Family SH-4A Series

Section 38 A/D Converter
38.7 Usage Notes
When using the A/D converter, note the points listed below.
38.7.1 Setting Analog Input Voltage
1. Analog input voltage range
During A/D conversion, the voltages input to the analog input pins ANn should be in the range
AVss ≤ ANn ≤ AVcc (n = 0 to 3).
2. AVcc and AVss input voltages
The AVcc and AVss input voltages should be as follows: AVcc = 3.3 V ± 0.3 V and AVss =
Vss. (AVcc = Analog power supply, AVss = Analog ground, Vss = Internal digital power
supply)
38.7.2 Processing of Analog Input Pins
To prevent damage from abnormal voltage such as voltage surges at the analog input pins (AN0 to
AN3), connect a protection circuit like the one shown in figure 38.6. The circuit shown also
includes a CR filter to suppress noise. This circuit is shown as an example; the circuit constants
should be determined according to actual application conditions.
AVcc
100 Ω
AN0 to AN3
*
0.1 µF
AVss
Note: * Bypass capacitor connected to AVcc
This LSI
10 µF
0.01 µF
Figure 38.6 Example of Analog Input Pin Protection Circuit
Rev. 1.00 Oct. 01, 2007 Page 1671 of 1956
REJ09B0256-0100