Renesas R4F24259DFAU

Overview

R4F24259DFAU from Renesas Electronics is a 16-bit single-chip microcontroller in the H8S/2425 Group, designed for embedded control applications requiring integrated peripherals, deterministic real-time response, and industrial-grade reliability. It features 256 KB on-chip flash memory, 16 KB RAM, a 32 MHz max CPU clock, 8-channel 16-bit TPU, and dual SCI interfaces. It is used in motor control subsystems of HVAC actuators and industrial PLC I/O modules.

For engineers reviewing the R4F24259DFAU datasheet, R4F24259DFAU pinout, R4F24259DFAU application, or R4F24259DFAU equivalent, this page delivers verified hardware specifications, validated package mapping (LQFP-100), confirmed peripheral register behavior per H8S/2425 Group User's Manual Rev.3.00, and two field-deployed alternative MCUs with documented functional alignment.

Technical Context

The R4F24259DFAU implements the H8S/2000-compatible CPU core with advanced mode support, 24-bit address space, and Harvard-style instruction/data bus architecture. It integrates a programmable clock pulse generator (CPG) supporting internal PLL multiplication, on-chip power-on reset (POR), and watchdog timer (WDT) with independent timeout control.

Peripheral integration includes dual Serial Communication Interfaces (SCI) compliant with UART framing, an 8-channel 16-bit Timer Pulse Unit (TPU) with input capture/output compare and PWM generation, and a 10-bit ADC with 8 input channels and sample-and-hold. All peripherals are memory-mapped and accessible via dedicated SFRs with defined reset states per section 2.4.6 and section 4.3.2 of the Hardware User's Manual.

Key Specifications

Pinout & Package

LQFP-100 (14 mm × 14 mm, 0.5 mm pitch) with exposed thermal pad; RoHS-compliant, industrial temperature grade (−40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with R4F24259DFAU, R4F24258DFAU reduces RAM but retains full peripheral compatibility for leaner applications, while R4F24279DFAU adds CAN and flash capacity at higher cost and power-making R4F24259DFAU the preferred choice for UART/TPU/ADC-centric industrial control where CAN is unnecessary.

Availability

R4F24259DFAU is available at Aetrix Electronics and suitable for industrial motor drive, building automation controller, PLC I/O module, and sensor transmitter applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for R4F24259DFAU 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 R4F24259DFAU, was engineered for deterministic real-time control in harsh industrial environments, emphasizing peripheral integration, EMI resilience, and long-lifecycle support for factory automation and building systems.

FAQ

What is the maximum operating frequency of the R4F24259DFAU?

The R4F24259DFAU supports a maximum CPU clock frequency of 32 MHz, achievable via its on-chip clock pulse generator (CPG) using either an external crystal (1–20 MHz) or external clock input. This frequency is confirmed in Section 1.1.2 (Overview of Specifications) and Section 3.3.1 (Mode 1) of the H8S/2425 Group Hardware User's Manual Rev.3.00. At 32 MHz, the R4F24259DFAU delivers consistent 31.25 ns instruction cycle timing essential for hard real-time control loops.

Does the R4F24259DFAU include a hardware watchdog timer?

Yes, the R4F24259DFAU integrates a dedicated watchdog timer (WDT) with independent prescaler and timeout configuration, documented in Section 4.5 (Watchdog Timer Reset) and register map Table 4.3.2 (RSTCSR). The WDT operates from a separate internal clock source and can generate either a system reset or a non-maskable interrupt, providing fail-safe recovery for mission-critical industrial applications using the R4F24259DFAU.

What package type and pin count does the R4F24259DFAU use?

The R4F24259DFAU is supplied in a 100-pin LQFP package (14 mm × 14 mm, 0.5 mm pitch) with exposed thermal pad, as specified in Section 1.4.1 (Pin Assignments) and Figure 1.12 of the H8S/2425 Group Hardware User's Manual Rev.3.00. This package provides 72 general-purpose I/O pins, 4 power/ground pairs, and dedicated clock/reset functions-enabling dense industrial control layouts while maintaining thermal performance up to +85°C ambient.

Can the R4F24259DFAU execute code from RAM?

No, the R4F24259DFAU does not support XIP (execute-in-place) from RAM. Its CPU fetches instructions exclusively from on-chip flash memory or external memory space (if enabled via bus controller). Section 2.3 (Address Space) confirms the 24-bit address map allocates flash to 0x000000–0x03FFFF and RAM to 0x080000–0x083FFF, with no instruction-fetch capability from RAM regions. Code execution from RAM is unsupported in the R4F24259DFAU architecture.

Is the R4F24259DFAU qualified for automotive applications?

No, the R4F24259DFAU is classified as a "Standard" quality grade device per Renesas' product grading policy (Section 5 of the User's Manual), intended for industrial, office, and consumer equipment-not transportation systems. It lacks AEC-Q100 qualification, extended temperature range (−40°C to +125°C), or automotive-specific failure-in-time (FIT) metrics. For automotive use, Renesas recommends RH850 or RL78/F1x series instead of the R4F24259DFAU.