Renesas R5F2123CJFP#W4

Overview

R5F2123CJFP#W4 from Renesas Electronics is a 16-bit R8C/23 Group microcontroller with CAN 2.0B interface, 128 KB program flash, 2×1 KB data flash, 6 KB RAM, and 12-channel 10-bit ADC - designed for automotive and industrial networking applications requiring embedded real-time control and robust bus communication.

For engineers reviewing the R5F2123CJFP#W4 datasheet, R5F2123CJFP#W4 pinout, R5F2123CJFP#W4 application, or R5F2123CJFP#W4 equivalent, this MCU delivers deterministic timing via 89-instruction R8C core, dual on-chip oscillators (high-speed adjustable + low-speed), integrated LIN and UART peripherals, and -40°C to +85°C operation in 48-pin LQFP.

Technical Context

The R5F2123CJFP#W4 implements the R8C CPU core with 20-bit address space (1 Mbyte), supporting single-chip operation and high-efficiency instruction execution at 50 ns min. cycle time (20 MHz XIN). It integrates dedicated hardware modules including Timer RA/RB (8-bit), Timer RD (16-bit ×2 with input capture/output compare), and Timer RE (compare match).

Peripheral integration includes one CAN 2.0B controller (16 message slots), one hardware LIN module (using Timer RA and UART0), two UART channels, two I²C interfaces, clock-synchronous serial I/O with chip select, and an on-chip voltage detection circuit with power-on reset - all managed via memory-mapped SFRs in the 00000h–002FFh and 01300h–0147Fh ranges.

Key Specifications

Pinout & Package

Package: 48-pin plastic LQFP (PLQP0048KB-A), 7 mm × 7 mm body, 0.5 mm pin pitch, exposed pad not specified.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microcontroller applications.

Compared with R5F2123CJFP#W4, R5F2123AJFP offers lower memory capacity at reduced cost for simpler applications, while R5F2123CKFP extends thermal range for harsher environments - neither provides pin-to-pin or functional substitution without validation of temperature and memory margins.

Availability

R5F2123CJFP#W4 is available at Aetrix Electronics and suitable for automotive body electronics, industrial CAN gateways, and motor control systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for R5F2123CJFP#W4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Renesas Electronics Corporation is a global semiconductor leader formed in 2010 through the merger of NEC Electronics and Renesas Technology, specializing in microcontrollers, analog, and power solutions.

The R5F2123CJFP#W4 belongs to the R8C/23 Group MCU family, engineered for cost-effective, real-time embedded control in automotive and industrial networks with integrated CAN, LIN, and data flash.

FAQ

What is the maximum operating frequency of the R5F2123CJFP#W4?

The R5F2123CJFP#W4 supports a maximum external crystal frequency of 20 MHz, achieving a minimum instruction execution time of 50 ns under VCC = 3.0–5.5 V conditions. Its high-speed on-chip oscillator is adjustable from 1 MHz to 20 MHz and can serve as the main system clock without external components.

Does the R5F2123CJFP#W4 include on-chip debug capability?

Yes, the R5F2123CJFP#W4 supports on-chip debugging via the single-wire background debugger interface. Emulator debug areas (20000h–23FFFh) are reserved in memory map and must be excluded from user code; debug functionality requires Renesas E8/E8a or E1 emulators.

How many CAN message buffers does the R5F2123CJFP#W4 support?

The R5F2123CJFP#W4 integrates one CAN 2.0B-compliant controller with 16 configurable message buffers (slots), supporting both standard (11-bit) and extended (29-bit) identifier formats, with programmable acceptance filtering and automatic retransmission.

What is the endurance rating of the data flash in the R5F2123CJFP#W4?

The R5F2123CJFP#W4 features two 1 KB data flash blocks rated for 10,000 write/erase cycles each, enabling reliable non-volatile storage of calibration data, device configuration, or runtime logs without external EEPROM.

Is the R5F2123CJFP#W4 pin-compatible with other R8C/23 Group MCUs?

Yes, all R8C/23 Group devices in the FP package (e.g., R5F21236JFP, R5F2123AJFP, R5F2123CJFP#W4) share identical 48-pin LQFP pinout and electrical characteristics - allowing hardware reuse across memory variants within the same temperature grade.