R5F21237DFP#U0 Renesas Electronics America, R5F21237DFP#U0 Datasheet - Page 516

• Manufacturer Part Number: R5F21237DFP#U0
• Description: IC R8C/23 MCU FLASH 48-LQFP
• Manufacturer: Renesas Electronics America
• Series: R8C/2x/23r

Specifications of R5F21237DFP#U0

• Core Processor: R8C
• Core Size: 16/32-Bit
• Speed: 20MHz
• Connectivity: CAN, 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): 2.7 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-LQFP
• For Use With: RCDK8C - KIT DEV EVAL FOR CAN R8C/23R0K521237S000BE - KIT DEV RSK R8C/23R0E521237CPE00 - EMULATOR COMPACT R8C/20/21/22/23
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

R8C/22 Group, R8C/23 Group
Rev.2.00 Aug 20, 2008
REJ09B0251-0200
22.10
22.10.1 Inserting a Bypass Capacitor between VCC and VSS Pins as a
22.10.2 Countermeasures against Noise Error of Port Control Registers
Connect the bypass capacitor (at least 0.1 µF) using the shortest and thickest as possible.
During severe noise testing, mainly power supply system noise, and introduction of external noise, the data of
port related registers may be changed.
As a firmware countermeasure, it is recommended to periodically reset the port registers, port direction
registers and pull-up control registers. However, examine fully before introducing the reset routine as conflicts
may be created between this reset routine and interrupt routines.
Notes on Noise
Countermeasure against Noise and Latch-up
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22. Usage Notes