M16C26A Datasheet, PDF (46/352 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/Tiny SERIES

M16C/26A Group (M16C/26A, M16C/26B, M16C/26T)
5. Reset
5.5 Voltage Detection Circuit
Note
VCC=5 V is assumed. Voltage Detection Circuit is not available in M16C/26T.
The voltage detection circuit has circuits to monitor the input voltage at the VCC pin, each checking the input
voltage with respect to Vdet3, and Vdet4, respectively. Use the VC26 to VC27 bits in the VCR2 register to
select whether or not to enable these circuits.
Use the reset level detection circuit for hardware reset 2.
The voltage down detection circuit can be set to detect whether the input voltage is equal to or greater than
Vdet4 or less than Vdet4 by monitoring the VC13 bit in the VCR1 register. Furthermore, a voltage down
detection interrupt can be generated.
RESET
VCR2 Register
b7 b6
CM10 Bit=1
(Stop Mode)
Reset level
detection circuit
+
>Vdet3
E
1 shot
>T
Brown-out Detect Reset
(Hardware Reset 2
Release Wait Time)
td(S-R)
Q
Internal Reset Signal
(“L” active)
VCC
+
>Vdet4
E
Low voltage
detection circuit
Figure 5.5.1. Voltage Detection Circuit Block
Noise Rejection
Low Voltage
Detect Signal
VCR1 Register
b3
VC13 Bit
Rev. 2.00 Feb.15, 2007 page 29 of 329
REJ09B0202-0200