Renesas DF38086RW4V

Overview

DF38086RW4V from Renesas Electronics is an H8/300H-based 16-bit single-chip microcomputer with 512 KB on-chip mask ROM, 32 KB RAM, and integrated peripherals including TPU (16-bit timer pulse unit), SCI (serial communication interface), and RTC. It operates at up to 20 MHz CPU clock, supports multiple low-power modes (subactive, subsleep, standby), and targets embedded control in industrial and office equipment.

For engineers reviewing the DF38086RW4V datasheet, DF38086RW4V pinout, DF38086RW4V application, or DF38086RW4V equivalent, key selection criteria include its 80-pin TQFP package, 3.3 V supply compatibility, on-chip flash programming support via SCI3 in boot mode, and interrupt controller with three configurable mask levels for deterministic real-time response.

Technical Context

The DF38086RW4V implements the H8/300H CPU core with full instruction set compatibility to H8/300, featuring a 16-bit data bus and 24-bit address space. Its system architecture includes dual clock domains: main oscillator (up to 20 MHz) and subclock (32.768 kHz or 38.4 kHz) for RTC and low-power timing.

Peripheral integration includes four SCIs (SCI0–SCI3), two 16-bit timer pulse units (TPU0/TPU1) supporting input capture, output compare, and PWM generation, and a watchdog timer (WDT) with independent clock source. The interrupt controller supports 25 internal/external sources with priority-based vectoring and programmable mask levels per source.

Key Specifications

Pinout & Package

DF38086RW4V is housed in an 80-pin TQFP package (PTQP0080KC-A), measuring 12 mm × 12 mm with 0.5 mm pitch. The package supports fine-pitch PCB layout while maintaining thermal and mechanical reliability for industrial applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DF38086RW4V, H8/38085R offers lower memory and cost for legacy-compatible upgrades, while R5F566TEADFP delivers 3× Dhrystone MIPS and integrated safety features - making it suitable for applications where DF38086RW4V's 16-bit architecture limits algorithm complexity or certification scope.

Availability

DF38086RW4V is available at Aetrix Electronics and suitable for industrial motor control, office equipment, energy metering interfaces, and factory automation I/O modules requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for DF38086RW4V 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 specializing in microcontrollers, analog, power, and SoC solutions for industrial, automotive, and infrastructure markets.

The H8/38086R Group belongs to Renesas' legacy H8 Family of 16-bit MCUs, designed specifically for cost-sensitive, low-to-medium complexity embedded control applications requiring robust real-time performance and long product lifecycles.

FAQ

What is the maximum operating frequency of the DF38086RW4V?

The DF38086RW4V supports a maximum CPU clock frequency of 20 MHz, achieved using an external 4.19 MHz crystal connected to OSC1/OSC2 with internal PLL multiplication. This allows instruction execution at 50 ns per cycle, enabling tight real-time control loops in motor and power conversion applications. The DF38086RW4V datasheet specifies this limit under 3.3 V supply and 85°C ambient conditions.

Does DF38086RW4V support in-system programming?

Yes, DF38086RW4V supports in-system programming via SCI3 (P41/RXD3 and P42/TXD3) in boot mode. This allows firmware updates without removing the device from the PCB. The process requires asserting the appropriate boot pins and using Renesas' Flash Development Toolkit (FDT) with a UART interface. DF38086RW4V does not support ISP through JTAG or SWD.

Which low-power modes are available on DF38086RW4V and what peripherals remain active?

DF38086RW4V offers four low-power modes: active (medium/high-speed), subactive, subsleep, and standby. In subsleep mode, the RTC, asynchronous event counter, and TPU retain state while CPU and most peripherals halt. In standby mode, only RTC and WDT remain functional with current draw below 10 µA. DF38086RW4V retains RAM contents across all modes except full reset.

Can DF38086RW4V be used with an external debugger like E8?

No - DF38086RW4V integrates an on-chip debugger that reserves pins NMI, P16, P36, and P37, and memory regions H'C000–H'CFFF and H'F380–H'F77F. External debuggers such as the E8 are incompatible. Debugging must use the built-in on-chip debugger via Renesas' High-performance Embedded Workshop or e2 studio with appropriate drivers. DF38086RW4V does not expose JTAG or cJTAG interfaces.

What is the function of the FROMCKSTP bit in CKSTPR1 for DF38086RW4V?

The FROMCKSTP bit (bit 1) in clock halt register 1 (CKSTPR1) controls the flash memory module's clock. When cleared to 0, the flash enters standby mode to reduce power consumption during idle periods. When set to 1, the flash clock remains active for read/write operations. DF38086RW4V requires FROMCKSTP = 1 during firmware updates and normal code execution; setting it to 0 is safe only when flash access is unnecessary.