Renesas R5F21322DNSP#U0

Overview

R5F21322DNSP from Renesas Electronics is an 8 KB Flash, 1 KB RAM 20-pin LSSOP microcontroller in the R8C/32D Group, featuring an R8C CPU core with 16×16-bit multiplier, 10-bit ×4-channel ADC, dual UART/I²C serial interfaces, and real-time clock (Timer RE). It operates from 1.8–5.5 V at up to 20 MHz and targets low-power embedded control in consumer appliances and office equipment.

For engineers reviewing the R5F21322DNSP datasheet, R5F21322DNSP pinout, R5F21322DNSP application, or R5F21322DNSP equivalent, this page delivers verified specifications, validated package mapping, confirmed peripheral functions (UART0/UART2/I²C/ADC/timers), ambient temperature range (−20°C to +85°C), and two documented alternative MCUs for design continuity.

Technical Context

The R5F21322DNSP implements the R8C CPU core with 89 fundamental instructions, 20-bit address space (1 Mbyte), and hardware multiplier supporting 16×16→32-bit multiply and MAC operations. Its memory map allocates 8 KB Flash (0E000h–0FFFFh) and 1 KB RAM (00400h–007FFh), with fixed interrupt vector table at 0FFDCh–0FFFFh.

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, and stop modes with current as low as 2.0 µA in stop mode at 3.0 V.

Key Specifications

Pinout & Package

Package: 20-pin LSSOP (PLSP0020JB-A, JEDEC MO-153 variant, 0.65 mm lead pitch, body size 7.6 × 4.4 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with R5F21322DNSP, R5F21324DNSP offers double Flash capacity for feature-rich firmware, while R5F21322DDSP provides extended temperature operation without altering code or PCB - both retain identical peripheral functionality and pinout.

Availability

R5F21322DNSP is available at Aetrix Electronics and suitable for home appliance control, office equipment interface, and consumer audio remote applications requiring stable component supply and long-term production continuity.

Supply support for R5F21322DNSP 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, and power solutions for industrial, automotive, and consumer markets.

The R5F21322DNSP belongs to the R8C/32D Group - a family of low-power, cost-optimized 8-bit MCUs designed for resource-constrained embedded control in appliances, office automation, and audio systems.

FAQ

What is the maximum operating frequency of the R5F21322DNSP and under what supply conditions?

The R5F21322DNSP achieves a maximum operating frequency of 20 MHz when powered at VCC = 2.7–5.5 V using the XIN clock source. At lower supply voltages (1.8–5.5 V), the maximum supported frequency reduces to 5 MHz to ensure timing margin and stability. This dual-frequency capability allows designers to optimize performance versus power consumption based on system requirements and battery state.

Does the R5F21322DNSP support in-circuit debugging and flash programming without external hardware?

Yes, the R5F21322DNSP includes on-chip debug functionality that enables full firmware debugging, breakpoint setting, and flash memory rewriting via a single-wire interface - no external emulator or debug probe is required. This capability is implemented in silicon and documented in the R8C/32D Group hardware manual, allowing rapid development and field firmware updates.

What are the key differences between the R5F21322DNSP and R5F21322DDSP variants?

The R5F21322DNSP and R5F21322DDSP share identical Flash (8 KB), RAM (1 KB), peripherals, and pinout. Their sole difference is operating ambient temperature range: R5F21322DNSP is rated for −20°C to +85°C (N grade), while R5F21322DDSP extends to −40°C to +85°C (D grade) for industrial or automotive cabin use. Firmware and PCB layout are fully interchangeable.

Can the R5F21322DNSP's UART2 module operate in I²C mode, and what pins are used?

Yes, UART2 on the R5F21322DNSP supports I²C-bus mode using pins P3_7 (SCL2), P3_4 (SDA2), and P3_3 (optional TRCCLK for clock stretching). Configuration is performed via U2MR and U2C0 registers. This dual-mode capability allows reuse of the same peripheral for either asynchronous serial or synchronous I²C communication - reducing pin count and simplifying system architecture.

How does the R5F21322DNSP handle power-on reset and brown-out detection?

The R5F21322DNSP integrates a voltage detection circuit with power-on reset (POR) and three configurable detection levels. Level 0 (VDD monitor) triggers reset during startup; Levels 1 and 2 provide programmable brown-out warnings or resets. Detection thresholds are selected via VD1LS register, and interrupt flags (VCMP1IC/VCMP2IC) allow firmware to initiate safe shutdown before supply collapse.