Renesas R5F21122FP#U0

Overview

R5F21122FP from Renesas Electronics is a 16-bit R8C/Tiny Series microcontroller in a 32-pin LQFP package, featuring an 8 KB flash program ROM, 512 bytes RAM, and dual 2 KB data flash blocks. It integrates a 10-bit 8-channel ADC, three 8-bit timers (X/Y/Z), one 16-bit Timer C with input capture, two UART channels (one clock-synchronous), and LED drive capability on P10–P17. It targets cost-sensitive embedded control in household appliances and industrial sensors.

For engineers reviewing the R5F21122FP datasheet, R5F21122FP pinout, R5F21122FP application, or R5F21122FP equivalent, key selection criteria include its -20°C to +85°C operating range, 3.0–5.5 V supply voltage, 62.5 ns minimum instruction cycle at 16 MHz, integrated data flash for parameter storage, and dedicated key interrupt inputs (KI0–KI3) for low-power wake-up in battery-operated devices.

Technical Context

The R5F21122FP implements the R8C/Tiny CPU core with 89 basic instructions and a 1 Mbyte linear address space. Its memory map allocates fixed interrupt vectors at 0FFDC₁₆–0FFFF₁₆, program ROM starting at 0C000₁₆, data flash at 02000₁₆–02FFF₁₆, and RAM from 00400₁₆. Two register banks support fast context switching during interrupts.

It features dual clock generation circuits: a main crystal/resonator oscillator (XIN/XOUT) and an on-chip oscillator, both supporting oscillation stop detection. The system supports four operating modes-single-chip, wait, stop, and debug-with power consumption as low as 0.7 µA in stop mode at 3.0 V.

Key Specifications

Pinout & Package

Package: PLQP0032GB-A (32-pin plastic LQFP, 7 mm × 7 mm, 0.8 mm pitch).

Key Features

Applications

Equivalent & Alternatives

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

Compared with R5F21122FP, R5F21123FP offers headroom for future firmware expansion while maintaining identical timing and I/O behavior, whereas R5F21122DFP delivers guaranteed operation at lower ambient temperatures without altering power or signal integrity design margins.

Availability

R5F21122FP is available at Aetrix Electronics and suitable for home appliance control, industrial sensor nodes, and office equipment requiring stable component supply and long-term production continuity.

Supply support for R5F21122FP 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 automotive, industrial, and IoT applications.

The R8C/12 Group, including R5F21122FP, was designed for cost-optimized 16-bit embedded control in consumer and general industrial systems where reliability, low power, and integrated peripherals reduce BOM count.

FAQ

What is the maximum operating frequency of the R5F21122FP?

The R5F21122FP operates at up to 16 MHz when supplied with 3.0–5.5 V, achieving a minimum instruction execution time of 62.5 ns. At 10 MHz, it supports a wider voltage range of 2.7–5.5 V. Frequency is determined by the external crystal or resonator connected to XIN/XOUT, or by the internal oscillator calibrated to ±1% accuracy.

Does the R5F21122FP support in-system programming (ISP)?

Yes, the R5F21122FP supports in-system programming via its single-wire on-chip debug interface. This allows firmware updates and calibration data writes to both program ROM and data flash without removing the device from the PCB. The R5F21122FP does not require high-voltage programming - all operations use standard VCC levels.

How many analog input channels does the R5F21122FP ADC support?

The R5F21122FP integrates a single 10-bit successive-approximation ADC with 8 selectable input channels (AN0 through AN7), mapped to port pins P00–P07. These channels share the same reference (VREF or AVCC) and conversion result register, supporting sequential or single-shot sampling with programmable trigger sources including timers and software start.

Can the R5F21122FP drive LEDs directly?

Yes, ports P10 through P17 on the R5F21122FP are designated LED drive ports capable of sinking up to 20 mA per pin. This allows direct connection of common-anode LEDs without external drivers, simplifying front-panel indicator designs in appliances and instrumentation.

What debug interface does the R5F21122FP provide?

The R5F21122FP provides a single-wire background debugger (BDM) interface compatible with Renesas E8/E8a emulators. It supports full-speed execution control, register and memory inspection, breakpoint setting, and flash programming - all using only the MODE pin and shared reset functionality, minimizing PCB footprint.