
R8C/38T-A Group
7. Voltage Detection Circuit
Under development Preliminary document
Specifications in this document are tentative and subject to change.
R01UH0241EJ0010 Rev.0.10
Page 59 of 730
Aug 05, 2011
7.
Voltage Detection Circuit
The voltage detection circuit is used to monitor the voltage applied to the VCC pin. The VCC input voltage can be
monitored by a program.
7.1
Overview
The detection voltage for voltage detection 0 can be selected from four levels with the OFS register.
The detection voltage for voltage detection 1 can be selected from sixteen levels with the VD1LS register.
The voltage monitor 0 reset and voltage monitor 1 and 2 interrupts can be used.
Table 7.1
Voltage Detection Circuit Specifications
Item
Voltage Monitor 0
Voltage Monitor 1
Voltage Monitor 2
VCC
monitor
Voltage to be
monitored
Vdet0
Vdet1
Vdet2
Detection target
Whether passing through
Vdet0 by falling
Whether passing through
Vdet1 by rising or falling
Whether passing through
Vdet2 by rising or falling
Detection voltage Selectable from 4 levels
with the OFS register
Selectable from 16 levels
with the VD1LS register
Fixed level
Monitor
None
The VW1C3 bit in the
VW1C register
The VW2C3 bit in the
VW2C register
Higher or lower than Vdet1 Higher or lower than Vdet2
Process at
voltage
detection
Reset
Voltage monitor 0 reset
None
Reset at Vdet0
VCC,
CPU operation is
restarted at VCC
Vdet0
Interrupts
None
Voltage monitor 1 interrupt
Voltage monitor 2 interrupt
Non-maskable or
maskable selectable
Non-maskable or
maskable selectable
Interrupt request at
Vdet1
VCC and/or
VCC
Vdet1
Interrupt request at
Vdet2
VCC and/or
VCC
Vdet2
Digital filter Switching
enabled/disabled
No digital filter function
Available
Sampling time
—
(fLOCO divided by n) × 2
n: 1, 2, 4, or 8
(fLOCO divided by n) × 2
n: 1, 2, 4, or 8