Renesas R5F21331DNFP#V2

Overview

R5F21331DNFP from Renesas is a 16-bit R8C CPU core MCU with 4 KB Flash, 1 KB RAM, 32-pin LQFP package, and operating temperature range of -20°C to +85°C. It integrates timer RA/RB/RC/RE, dual UART (UART0/UART2 with I²C mode), 10-bit 12-channel ADC, comparator B, voltage detection, and on-chip oscillators for embedded control in consumer appliances and office equipment.

For engineers reviewing the R5F21331DNFP datasheet, R5F21331DNFP pinout, R5F21331DNFP application, or R5F21331DNFP equivalent, key selection criteria include its 4 KB Flash capacity, 32-pin PLQP0032GB-A package, 10-bit ADC with sweep mode, UART2 I²C-bus compatibility, and support for wait/stop low-power modes with sub-µA current draw.

Technical Context

The R5F21331DNFP implements the R8C CPU core with 89 fundamental instructions, 16×16→32-bit hardware multiplier, and 20-bit address space (1 Mbyte). Its interrupt system supports 69 vectors across 7 priority levels, including external INT0/INT1/INT3 and key input KI0–KI3.

Clock generation includes four independent circuits: XIN/XOUT (up to 20 MHz), XCIN/XCOUT (32 kHz), high-speed on-chip oscillator (adjustable), and low-speed on-chip oscillator - all selectable via software-controlled frequency dividers (1/2/4/8/16) and usable in standard/wait/stop modes.

Key Specifications

Pinout & Package

32-pin LQFP package (PLQP0032GB-A, formerly 32P6U-A), 7 mm × 7 mm body, 0.8 mm pin pitch, exposed pad not specified. Pin functions include dedicated analog inputs (AN0–AN11), programmable I/O ports (P0–P4), and multifunction pins supporting UART, I²C, timers, and A/D triggers.

Key Features

Applications

Equivalent & Alternatives

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

Compared with R5F21331DNFP, the R5F21332DNFP offers double Flash capacity for enhanced firmware scalability, while the R5F21331DDFP provides wider temperature tolerance without altering code or layout - both retain identical pinout, peripheral configuration, and debug infrastructure.

Availability

R5F21331DNFP is available at Aetrix Electronics and suitable for home appliance control, office equipment interface, audio system remote interface, and consumer device power management requiring stable component supply across production lifecycles.

Supply support for R5F21331DNFP 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/33D Group, including R5F21331DNFP, was designed for cost-sensitive, low-power embedded control in consumer electronics - emphasizing integration of analog peripherals, robust EMI performance, and simplified development with on-chip debug.

FAQ

What is the maximum operating frequency of the R5F21331DNFP?

The R5F21331DNFP supports a maximum operating frequency of 20 MHz when powered at 2.7–5.5 V using the XIN clock input. At lower voltages (1.8–5.5 V), it operates up to 5 MHz. The minimum instruction execution time is 50 ns under 20 MHz conditions, enabling responsive real-time control in appliance and office equipment applications.

Does the R5F21331DNFP support I²C communication?

Yes, the R5F21331DNFP supports I²C-bus communication through UART2's dedicated I²C mode on pins P3_4 (SCL2) and P3_7 (SDA2). This allows direct connection to I²C sensors, EEPROMs, or power management ICs without external bus controllers - a key feature confirmed in the R8C/33D Group datasheet section 1.1.2 and Table 1.1.

What is the purpose of the ADTRG pin on the R5F21331DNFP?

The ADTRG pin (P4_5) on the R5F21331DNFP serves as an external hardware trigger for the 10-bit A/D converter. When asserted, it initiates a conversion sequence without CPU intervention - critical for synchronized sampling in motor control or audio preprocessing. This function is documented in Table 1.4 and Section 1.5 of the R8C/33D Group datasheet.

Can the R5F21331DNFP operate from a 3.3 V supply?

Yes, the R5F21331DNFP operates reliably from a 3.3 V supply across its full temperature range (-20°C to +85°C). At 3.0 V and 10 MHz, typical current consumption is 3.5 mA; in wait mode with 32 kHz XCIN clock, it draws only 3.5 µA - making it well-suited for battery-backed or energy-conscious designs.

How many interrupt sources does the R5F21331DNFP support?

The R5F21331DNFP supports 69 interrupt vectors with 7 programmable priority levels. Sources include 7 external interrupts (INT0–INT3, KI0–KI3), peripheral interrupts (UART0/UART2, Timer RA/RB/RC/RE, ADC, comparator, voltage detection), and system events (oscillation stop, watchdog timeout). This structure is defined in Table 1.1 and Section 2.8.9 of the official datasheet.