Renesas R5F2134CXJFP 16-bit R8C Microcontroller
The Renesas R5F2134CXJFP is a 16-bit microcontroller from the R8C/34X series, based on the R8C CPU core. This device is part of Renesas Electronics' comprehensive portfolio of microcontrollers for automotive, industrial, and consumer applications requiring a balance of performance, memory, peripheral integration, and low power consumption. The R5F2134CXJFP offers an extensive set of communication interfaces, analog peripherals, and timer functions, making it suitable for use in motor control systems, automotive body electronics, sensor interfaces, industrial controllers, and home appliance applications.
Processor Core and Performance
The R8C CPU core operates at a maximum clock frequency of 20 MHz, executing a rich instruction set of 89 fundamental instructions optimized for control-oriented applications. The 16‑bit core provides efficient handling of both 8‑bit and 16‑bit data types, and the multiply and divide instructions accelerate arithmetic operations common in motor control and sensor processing algorithms. The device includes an internal oscillator that can serve as the main clock source, reducing external component count in cost-sensitive applications.
Memory Architecture
The R5F2134CXJFP provides 128 kilobytes of on-chip flash memory for program storage, organized as 128K by 8 bits. This flash memory supports in-circuit programming and in-application programming, allowing firmware updates to be performed without removing the device from the target system. Data retention is specified for up to 20 years with minimal degradation when operated within the device's voltage and temperature ranges. The device includes 10 kilobytes of RAM for data storage, stack operations, and variable retention. The RAM size supports moderate-complexity control algorithms and buffering of sensor data prior to processing or transmission.
Analog-to-Digital Converter
An integrated 10-bit analog-to-digital converter provides 12 multiplexed input channels, allowing the microcontroller to directly read analog sensors such as potentiometers, temperature sensors, photodetectors, and current sensors without requiring an external ADC. The ADC includes a sample-and-hold circuit and supports both single conversion and scan conversion modes. Conversion can be triggered by software, internal timers, or external events, enabling synchronized sampling in real-time control applications such as motor commutation or power supply monitoring. The 10-bit resolution provides sufficient granularity for many control applications while conserving code space compared to higher-resolution converters.

Communication Interfaces
The R5F2134CXJFP offers a comprehensive set of serial communication interfaces for networking and device-to-device communication. A CANbus controller is integrated, supporting the CAN 2.0B protocol for automotive and industrial control networks requiring robust, error-tolerant messaging. An I2C bus interface enables connection to many common peripheral devices including EEPROMs, temperature sensors, RTCs, and I/O expanders. LINbus support allows the device to function as a master or slave on Local Interconnect Networks common in automotive body electronics. The device also includes SIO (Serial I/O), SSU (Synchronous Serial Unit), and UART/USART interfaces for general-purpose serial communication. The UARTs support full-duplex asynchronous communication with programmable baud rates, and can be used to interface with RS‑232, RS‑485, or other serial devices with appropriate external line drivers.
Timer and PWM Functions
Multiple integrated timers support diverse timing and pulse-width modulation requirements. Pulse Width Modulator outputs allow the generation of variable duty-cycle signals for motor speed control, dimming of indicator LEDs, or generation of analog signals through an external RC filter. Watchdog Timer is provided to detect software execution errors and reset the microcontroller if the software fails to service the timer within a specified window. The devices include power-on reset and voltage detection for brown‑out protection.
Package and Pinout
The R5F2134CXJFP is offered in a 48-pin LQFP (Low‑profile Quad Flat Package) with a body size of 7×7 millimeters. The package is RoHS compliant, meeting European environmental requirements for hazardous substances. Pin pitch is appropriate for hand soldering or reflow assembly processes commonly used in electronics manufacturing. The 43 I/O pins provide sufficient interface capacity for connecting external switches, relays, sensors, LED indicators, and other system peripherals.
Operating Conditions and Power Supply
The microcontroller operates from a single supply voltage of 2.7 V to 5.5 V DC, allowing compatibility with both 3.3 V and 5 V system architectures. This wide supply range simplifies power supply design and allows the device to be used in battery‑powered applications and industrial control systems powered from 24 V with appropriate local regulation. Operating temperature range is -40°C to 85°C, making the device suitable for automotive under‑hood use, outdoor industrial enclosures, and high‑ambient process environments. The device includes multiple power‑saving modes, including wait mode and stop mode, which drastically reduce current consumption when the CPU is idle and permit battery‑operated applications or energy‑conserving designs.
Peripheral Features
The R5F2134CXJFP includes a programmable I/O system that allows each port pin to be configured as input, output, or peripheral function. Pin functions can be reassigned to support different peripheral multiplexing options, increasing design flexibility in board layout. The on‑chip debug function supports software development and in‑system debugging using a compatible emulator, facilitating firmware development without requiring special debug hardware ports beyond those available on the production device. The device's internal architecture eliminates the need for many external components, reducing total system cost and board area.
Applications and Target Markets
The R5F2134CXJFP is well‑suited for applications requiring a cost‑effective yet capable 16‑bit microcontroller. Typical target markets include automotive body control modules for window lifts, door locks, mirror adjustment, seat control, lighting control. Industrial applications include programmable logic controller I/O modules, sensor interfaces, conveyor controllers, small motor drives. Consumer applications include air conditioner controllers, washing machine controls, microwave ovens, battery management systems for power tools, and Internet of Things edge devices.




