R8C/20 Group, R8C/21 Group 6. Voltage Detection Circuit
Rev.2.00 Aug 27, 2008 Page 28 of 458
REJ09B0250-0200
6. Voltage Detection Circuit
The voltage detection circuit is a circuit to monitor the input voltage to the VCC pin. This circuit monitors the VCC
input voltage by the program. And the voltage monitor 1 reset, voltage monitor 2 interrupt and voltage monitor 2 reset
can be used.
Table 6.1 lists the Specifications of Voltage Detection Circuit and Figures 6.1 to 6.3 show the Block Diagrams.
Figures 6.4 to 6.6 show the Associated Registers.
Table 6.1 Specifications of Voltage Detection Circuit
Item Voltage Detection 1 Voltage Detection 2
VCC Monitor Voltage to monitor Vdet1 Vdet2
Detection target Whether passing
through Vdet1 by rising
or falling
Whether passing
through Vdet2 by rising
or falling
Monitor None VCA13 bit in VCA1
register
Whether VCC is higher
or lower than Vdet2
Process When Voltage Is
Detected
Reset Voltage monitor 1 reset Voltage monitor 2 reset
Reset at Vdet1 > VCC;
Restart CPU operation at
VCC > Vdet1
Reset at Vdet2 > VCC
Restart CPU operation
after a specified time
Interrupt None Voltage monitor 2
interrupt
Interrupt request at
Vdet2 > VCC and VCC >
Vdet2 when digital filter
is enabled;
Interrupt request at
Vdet2 > VCC or VCC >
Vdet2 when digital filter
is disabled
Digital Filter Switch
enabled/disabled
Available Available
Sampling time (Divide-by-n of fOCO-S)
x 4
n: 1, 2, 4 and 8
(Divide-by-n of fOCO-S)
x 4
n: 1, 2, 4 and 8
To Next Page
Loading...
Need help?
General
