r5f21368sdfp Renesas Electronics Corporation., r5f21368sdfp Datasheet - Page 86

• Manufacturer Part Number: r5f21368sdfp
• Description: Renesas Mcu R8c Family / R8c/3xt-a Series
• Manufacturer: Renesas Electronics Corporation.

Under development
R8C/36T-A Group
R01UH0240EJ0001 Rev.0.01
Apr 28, 2011
7.
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
Table 7.1
VCC
monitor
Process at
voltage
detection
Digital filter Switching
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 lists the Voltage Detection Circuit Specifications. Figure 7.1 shows the Voltage Detection Circuit Block
Diagram. Figure 7.2 shows the Voltage Monitor 0 Reset Generation Circuit Block Diagram. Figure 7.3 shows the
Voltage Monitor 1 Interrupt Generation Circuit Block Diagram. Figure 7.4 shows the Voltage Monitor 2 Interrupt
Generation Circuit Block Diagram.
Voltage Detection Circuit
Overview
Item
Voltage to be
monitored
Detection target
Detection voltage Selectable from 4 levels
Monitor
Reset
Interrupts
enabled/disabled
Sampling time
Preliminary document
Specifications in this document are tentative and subject to change.
Voltage Detection Circuit Specifications
Whether passing through
Vdet0
Vdet0 by falling
with the OFS register
None
Voltage monitor 0 reset
Reset at Vdet0  VCC,
CPU operation is
restarted at VCC  Vdet0
None
No digital filter function
—
Voltage Monitor 0
Vdet1
Whether passing through
Vdet1 by rising or falling
Selectable from 16 levels
with the VD1LS register
The VW1C3 bit in the
VW1C register
Higher or lower than Vdet1 Higher or lower than Vdet2
None
Voltage monitor 1 interrupt
Non-maskable or
maskable selectable
Interrupt request at
Vdet1  VCC and/or
VCC  Vdet1
Available
(fLOCO divided by n) × 2
n: 1, 2, 4, or 8
Voltage Monitor 1
Vdet2
Whether passing through
Vdet2 by rising or falling
Fixed level
The VW2C3 bit in the
VW2C register
None
Voltage monitor 2 interrupt
Non-maskable or
maskable selectable
Interrupt request at
Vdet2  VCC and/or
VCC  Vdet2
Available
(fLOCO divided by n) × 2
n: 1, 2, 4, or 8
7. Voltage Detection Circuit
Voltage Monitor 2
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