M30622MA-XXXFP RENESAS [Renesas Technology Corp], M30622MA-XXXFP Datasheet - Page 419

• Manufacturer Part Number: M30622MA-XXXFP
• Description: 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY
• Manufacturer: RENESAS [Renesas Technology Corp]

A-D Converter
404
Figure 2.7.22. Use of capacitors to reduce noice
2.7.10 Precautions for A-D Converter
(1) Write to each bit (except bit 6) of A-D control register 0, to each bit of A-D control register 1,
(2) To reduce conversion error due to noise, connect a voltage to the AVcc pin and to the Vref pin from
(3) Set the direction register of the following ports to input: the port corresponding to a pin to be
(4) In using a key-input interrupt, none of the 4 pins (AN
(5) If using the A-D converter with Vcc = 2.7V to 4.0 V:
(6) Rewrite to analog input pin after changing A-D operation mode. The two cannot be set at the
(7) When using the one-shot or single sweep mode
(8) When using the repeat mode or repeat sweep mode 0 or 1
(9) Use AD under 10 MHz. When X
and to bit 0 of A-D control register 2 when A-D conversion is stopped (before a trigger occurs).
In particular, when the Vref connection bit is changed from 0 to 1, start A-D conversion after
an elapse of 1 s or longer.
an independent source. It is recommended to connect a capacitor between the AVss pin and the
AVcc pin, between the AVss pin and the Vref pin, and between the AVss pin and the analog input
pin (ANi). Figure 2.7.22 shows the an example of connecting the capacitors to these pins.
used as an analog input pin and external trigger input pin (P9
conversion port (if the A-D input voltage goes to “L” level, a key-input interrupt occurs).
same time.
Microcomputer
Use only a divided frequency for f
Select without the Sample & Hold feature.
Select 8-bit mode.
Confirm that A-D conversion is complete before reading the A-D register.
(Note: When A-D conversion interrupt request bit is set, it shows that A-D conversion is completed.)
Use the undivided main clock as the internal CPU clock.
AV
AV
V
V
REF
AN
CC
CC
SS
i
C1
C3
C2
Note
Note
IN
is over 10 MHz, divide it.
1:
2:
AD
C1 0.47 µF, C2 0.47 µF, C3 100 pF
(for reference)
Use thick and shortest possible wiring
to connect capacitors.
(undivided f
AD
4
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
through AN
is not allowed).
7
).
7
) can be used as an A-D
Mitsubishi microcomputers
M16C / 62 Group