Renesas R4F24255NFPU

Overview

R4F24255NFPU from Renesas Electronics is a 16-bit single-chip microcontroller in the H8S/2425 Group, featuring an H8S/2400 Series CPU core, 512 KB on-chip Flash memory, 32 KB RAM, and integrated peripherals including TPU (16-bit timer pulse unit), SCI (serial communication interface), WDT (watchdog timer), and CPG (clock pulse generator). It operates at up to 33 MHz and targets industrial control and embedded automation systems requiring deterministic real-time response.

For engineers reviewing the R4F24255NFPU datasheet, R4F24255NFPU pinout, R4F24255NFPU application, or R4F24255NFPU equivalent, key selection criteria include its 100-pin LQFP package, 3.3 V supply compatibility, Flash endurance of 10,000 write/erase cycles, built-in JTAG debugging interface, and support for multiple low-power operating modes including software standby and stop modes.

Technical Context

The R4F24255NFPU implements the H8S/2400 CPU architecture with 24-bit address space, 16-bit data bus, and instruction set backward-compatible with H8/300H. It integrates a programmable clock pulse generator supporting internal PLL multiplication (×1 to ×4) and multiple clock sources (main oscillator, sub-oscillator, internal RC).

Peripheral subsystems include dual TPU channels with input capture/output compare/PWM generation, two full-duplex SCIs with framing error detection and baud rate generation, and a watchdog timer with independent clock source and windowed timeout capability. Memory protection is enforced via on-chip memory management logic for Flash and RAM regions.

Key Specifications

Pinout & Package

Package: 100-pin LQFP (14 mm × 14 mm, 0.5 mm pitch), thermally enhanced with exposed thermal pad (EP). Pin 1 marked by dot; pin numbering follows standard counter-clockwise convention starting from top-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit microcontroller applications.

Compared with R4F24255NFPU, R4F24257NFPU offers seamless upgrade path within same footprint and software ecosystem, while R4F24275NFPU introduces architectural enhancements that increase performance but demand hardware and firmware revalidation.

Availability

R4F24255NFPU is available at Aetrix Electronics and suitable for industrial PLC I/O modules, motor control drives, building energy management systems, and smart meter data concentrators requiring stable component supply across extended product lifecycles.

Supply support for R4F24255NFPU 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 Japanese semiconductor manufacturer specializing in microcontrollers, analog, and power devices for industrial, automotive, and infrastructure markets.

The H8S/2425 Group, including R4F24255NFPU, was designed for deterministic real-time control in cost-sensitive industrial equipment where reliability, long-term availability, and toolchain maturity outweigh raw processing throughput.

FAQ

What is the maximum operating frequency of the R4F24255NFPU?

The R4F24255NFPU operates at a maximum frequency of 33 MHz when supplied with 3.3 V and using the internal PLL configured for ×4 multiplication of a 8.25 MHz crystal. This frequency is guaranteed across the full −40 °C to +85 °C temperature range and defines the upper limit for instruction execution timing and peripheral clock derivation in the R4F24255NFPU.

Does the R4F24255NFPU support in-system programming (ISP)?

Yes, the R4F24255NFPU supports in-application programming (IAP) of its on-chip Flash memory via the built-in bootloader and dedicated Flash control registers. This allows firmware updates in the field without requiring external programming hardware, provided the application reserves protected boot sectors and manages erase/write sequencing per Renesas' Flash specification for the R4F24255NFPU.

What debug interfaces does the R4F24255NFPU provide?

The R4F24255NFPU provides IEEE 1149.1-compliant JTAG interface for boundary-scan testing, on-chip debugging, and flash programming. It supports full visibility into CPU registers, memory, and peripheral control registers during active execution, enabling breakpoints, watchpoints, and real-time variable inspection - all native to the R4F24255NFPU silicon implementation.

Is the R4F24255NFPU pin-compatible with other H8S/2425 Group members?

Yes, the R4F24255NFPU shares identical pin assignment and electrical characteristics with other 100-pin LQFP variants in the H8S/2425 Group, including R4F24257NFPU and R4F24259NFPU. This allows direct substitution within the same package footprint without PCB modification, provided firmware accommodates differences in Flash size and optional features.

What low-power modes are available on the R4F24255NFPU?

The R4F24255NFPU supports four low-power modes: Wait (CPU halted, peripherals active), Stop (CPU and most peripherals halted, RAM retained), Software Standby (selected clocks stopped, RAM retained), and Deep Software Standby (minimal current draw, RTC and wakeup logic active). Each mode offers distinct trade-offs between wake-up latency and current consumption, configurable via SYSCR and MDCR registers in the R4F24255NFPU.