![Renesas R8C series Скачать руководство пользователя страница 178](http://html1.mh-extra.com/html/renesas/r8c-series/r8c-series_hardware-manual_1440345178.webp)
R8C/18 Group, R8C/19 Group
16. Comparator
Rev.1.30
Apr 14, 2006
Page 163 of 233
REJ09B0222-0130
16. Comparator
The comparator compares the electric potential input from the VREF pin with analog input.
The analog input shares pins P1_0
to P1_3. Therefore, when using these pins, ensure the corresponding
port direction bits are set to 0 (input mode).
The result of comparator conversion is stored in the AD register.
Table 16.1 lists the Comparator Performance. Figure 16.1 shows a Comparator Block Diagram.
Figures 16.2 and 16.3 show the Associated Comparator Registers.
NOTE:
1. The
φ
AD frequency must be 10 MHz or below.
Table 16.1
Comparator Performance
Item
Performance
Comparator conversion
method
Comparator
Analog input voltage
0 V to AVCC
Operating clock
φ
4.2 V
≤
AVCC
≤
5.5 V fRING-fast, f1, f2, f4
2.7 V
≤
AVCC < 4.2 V f2, f4
Absolute accuracy
AVCC = 2.7 to 5.5 V ± 20 mV
Operating mode
One-shot and repeat modes
Analog input pin
4 pins (AN8 to AN11)
Comparator conversion start
conditions
• Software trigger
Set the ADST bit in the ADCON0 register to 1 (comparator conversion
starts).
• Capture
A timer Z interrupt request is generated while the ADST bit is set to 1.
Conversion rate per pin
10
φ
AD cycles