R5F21257SNFP#U0 Renesas Electronics America, R5F21257SNFP#U0 Datasheet - Page 52

• Manufacturer Part Number: R5F21257SNFP#U0
• Description: IC R8C/25 MCU FLASH 52LQFP
• Manufacturer: Renesas Electronics America
• Series: R8C/2x/25r

Specifications of R5F21257SNFP#U0

• Core Processor: R8C
• Core Size: 16/32-Bit
• Speed: 20MHz
• Connectivity: I²C, LIN, SIO, SSU, UART/USART
• Peripherals: POR, Voltage Detect, WDT
• Number Of I /o: 41
• Program Memory Size: 48KB (48K x 8)
• Program Memory Type: FLASH
• Ram Size: 2.5K x 8
• Voltage - Supply (vcc/vdd): 2.2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 52-LQFP
• For Use With: R0K521256S000BE - KIT EVAL STARTER FOR R8C/25
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

R8C/24 Group, R8C/25 Group
Rev.3.00
REJ09B0244-0300
6.
The voltage detection circuit monitors the input voltage to the VCC pin. This circuit can be used to monitor the VCC
input voltage by a program. Alternately, voltage monitor 0 reset, voltage monitor 1 interrupt, voltage monitor 1 reset,
voltage monitor 2 interrupt, and voltage monitor 2 reset can also be used.
Table 6.1 lists the Specifications of Voltage Detection Circuit and Figures 6.1 to 6.4 show the Block Diagrams. Figures
6.5 to 6.8 show the Associated Registers.
Table 6.1
VCC Monitor
Process
When Voltage
is Detected
Digital Filter
Voltage Detection Circuit
Feb 29, 2008
Item
Specifications of Voltage Detection Circuit
Voltage to monitor
Detection target
Monitor
Reset
Interrupt
Switch
enabled/disabled
Sampling time
Page 33 of 485
Vdet0
Whether passing
through Vdet0 by rising
or falling
None
Reset at Vdet0 > VCC;
restart CPU operation
at VCC > Vdet0
None
Available
(Divide-by-n of fOCO-S)
× 4
n: 1, 2, 4, and 8
Voltage monitor 0 reset
Voltage Detection 0
Voltage monitor 1
Vdet1
Passing through Vdet1 by
rising or falling
VW1C3 bit in VW1C
register
Whether VCC is higher or
lower than Vdet1
Voltage monitor 1 reset
Reset at Vdet1 > VCC;
restart CPU operation
after a specified time
interrupt
Interrupt request at Vdet1
> VCC and VCC > Vdet1
when digital filter is
enabled;
interrupt request at Vdet1
> VCC or VCC > Vdet1
when digital filter is
disabled
Available
(Divide-by-n of fOCO-S)
× 4
n: 1, 2, 4, and 8
Voltage Detection 1
6. Voltage Detection Circuit
Vdet2
Passing through Vdet2 by
rising or falling
VCA13 bit in VCA1
register
Whether VCC is higher or
lower than Vdet2
Voltage monitor 2 reset
Reset at Vdet2 > VCC;
restart CPU operation
after a specified time
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
Available
(Divide-by-n of fOCO-S)
× 4
n: 1, 2, 4, and 8
Voltage Detection 2