Renesas R5F21331CDFP#V2

Overview

R5F21331CDFP#V2 from Renesas Electronics is a 16-bit R8C CPU core microcontroller with 4 KB flash program ROM, 512 bytes RAM, and 4 KB data flash (1 KB × 4 blocks) supporting background operation (BGO). It operates at up to 20 MHz (VCC = 2.7–5.5 V), features 12-channel 10-bit A/D conversion, dual 8-bit D/A outputs, and hardware LIN bus support via Timer RA and UART0 - deployed in consumer audio equipment and office automation systems.

For engineers reviewing the R5F21331CDFP#V2 datasheet, R5F21331CDFP#V2 pinout, R5F21331CDFP#V2 application, or R5F21331CDFP#V2 equivalent, key selection criteria include its -40°C to +85°C industrial temperature grade (D version), 32-pin LQFP package (PLQP0032GB-A), integrated voltage detection circuitry, and real-time clock (Timer RE) with weekday-aware timekeeping.

Technical Context

The R5F21331CDFP#V2 implements the R8C CPU core with 89 fundamental instructions and a dedicated 16×16→32-bit multiplier for efficient signal processing. Its memory map spans 1 Mbyte (00000h–FFFFFh), with fixed interrupt vector table at 0FFDCh–0FFFFh and data flash mapped to 03000h–03FFFh.

It integrates four independent clock sources: XIN/XOUT (up to 20 MHz), XCIN/XCOUT (32 kHz), high-speed on-chip oscillator (adjustable), and low-speed on-chip oscillator - enabling flexible power management across standard, wait (3.5 µA @ 3.0 V), and stop (2.0 µA @ 3.0 V) modes.

Key Specifications

Pinout & Package

Package: 32-pin LQFP (PLQP0032GB-A), 7 mm × 7 mm body, 0.8 mm pin pitch, surface-mount compatible.

Key Features

Applications

Equivalent & Alternatives

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

Compared with R5F21331CNFP, the R5F21331CDFP#V2 provides guaranteed operation down to -40°C - critical for factory automation panels. Against R5F21332CDFP, it trades ROM headroom for lower cost and footprint efficiency in resource-constrained designs.

Availability

R5F21331CDFP#V2 is available at Aetrix Electronics and suitable for audio equipment control, office automation devices, consumer appliance UI, and industrial sensor hub applications requiring stable component supply across long production lifecycles.

Supply support for R5F21331CDFP#V2 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 automotive, industrial, and IoT markets.

The R8C/33C Group, including R5F21331CDFP#V2, was designed for cost-sensitive, low-power embedded control in consumer electronics - emphasizing integration of A/D, D/A, LIN, and real-time clock to reduce BOM count and PCB area.

FAQ

What is the maximum operating frequency of the R5F21331CDFP#V2 and under what supply conditions?

The R5F21331CDFP#V2 achieves a maximum operating frequency of 20 MHz when powered at VCC = 2.7 V to 5.5 V, with minimum instruction execution time of 50 ns. At reduced supply voltages (1.8 V to 5.5 V), the maximum frequency drops to 5 MHz (200 ns min. instruction time), enabling flexible power/performance trade-offs in battery-powered applications.

Does the R5F21331CDFP#V2 support in-circuit debugging and flash reprogramming?

Yes, the R5F21331CDFP#V2 includes on-chip debug capability and on-board flash rewrite functionality. It supports full-cycle programming and erasure of both program ROM (1,000 cycles) and data flash (10,000 cycles) without requiring external programmers - enabling field firmware updates and development iteration directly through the on-chip debug interface.

How does the background operation (BGO) function work in the R5F21331CDFP#V2 data flash?

The R5F21331CDFP#V2 data flash supports background operation (BGO), allowing the CPU to execute code from program ROM while simultaneously erasing or writing to data flash blocks. This enables seamless firmware updates, parameter logging, or calibration storage without interrupting real-time control loops - critical for uninterrupted operation in audio or motor control systems.

What peripheral resources are allocated to LIN bus communication on the R5F21331CDFP#V2?

The R5F21331CDFP#V2 implements hardware LIN 2.0 using Timer RA for baud rate generation and pulse shaping, combined with UART0 for data framing and error checking. Pins P1_6 (CLK0), P1_4 (TXD0), and P1_5 (RXD0) are dedicated to this function, eliminating need for external LIN transceivers in compliant automotive and industrial subnetworks.

Can the R5F21331CDFP#V2 operate from a 32 kHz crystal alone, and what functions remain active in stop mode?

Yes, the R5F21331CDFP#V2 can run exclusively from the 32 kHz XCIN/XCOUT crystal in stop mode, consuming only 2.0 µA at 3.0 V. In this state, Timer RE (real-time clock), watchdog timer (with low-speed oscillator), and voltage detection circuit remain functional - enabling wake-up on time-of-day alarms, supply faults, or external interrupts while preserving battery life.