Renesas R5F21102FP#U0

Overview

R5F21102FP from Renesas Electronics is a 16-bit CMOS microcontroller in the R8C/10 Group, built on the R8C/Tiny Series CPU core. It features 8 KB flash memory, 512 bytes RAM, 10-bit 8-channel ADC, three 8-bit timers (X/Y/Z), one 16-bit timer C with input capture, dual UART interfaces (one clock-synchronous), and operates from 2.7–5.5 V across –20 to +85 °C. It targets embedded control in household appliances and industrial sensors.

For engineers reviewing the R5F21102FP datasheet, R5F21102FP pinout, R5F21102FP application, or R5F21102FP equivalent, key selection considerations include its LQFP-32 package, integrated LED drive ports (P10–P17), low-power Stop mode (0.7 µA), and dual serial interface capability for sensor-to-host communication and diagnostics.

Technical Context

The R5F21102FP implements the R8C/Tiny CPU core with 89 basic instructions and executes at 62.5 ns minimum instruction time (16 MHz XIN, 3.0–5.5 V). Its memory map allocates 1 MB address space, with fixed interrupt vectors at 0FFDC₁₆–0FFFF₁₆, flash starting at 0C000₁₆, and RAM beginning at 00400₁₆.

Peripheral integration includes two independent UART modules (U0MR/U1MR configurable), a 10-bit A/D converter with internal reference (VREF tied to VCC), and dedicated key-input interrupt pins (KI0–KI3) supporting wake-up from low-power modes. The on-chip oscillator and main clock circuit support ceramic resonator or crystal operation.

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 16-bit microcontroller applications.

Compared with R5F21103FP and R5F21102DFP, the R5F21102FP provides optimal balance of flash/RAM capacity and commercial-temperature qualification for cost-sensitive appliance and sensor applications - avoiding over-specification while maintaining full peripheral compatibility.

Availability

R5F21102FP 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 R5F21102FP 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 formed in 2010 through the merger of NEC Electronics and Renesas Technology, specializing in microcontrollers, analog, and power solutions.

The R8C/10 Group targets cost-effective, low-power embedded control in consumer and industrial applications, emphasizing integrated peripherals, small footprint, and robust operation across commercial temperature ranges.

FAQ

What is the maximum operating frequency of the R5F21102FP?

The R5F21102FP achieves a minimum instruction execution time of 62.5 ns when operating at 16 MHz with VCC = 3.0–5.5 V. At 10 MHz and VCC = 2.7–5.5 V, the minimum instruction time is 100 ns. The device supports external crystal/resonator frequencies up to 20 MHz, but timing specifications are guaranteed only up to 16 MHz under specified voltage conditions. The R5F21102FP does not support PLL-based frequency multiplication.

Does the R5F21102FP support in-circuit debugging?

Yes, the R5F21102FP supports on-chip debugging via dedicated pins (P00/AN7/TxD11 and P37/TxD10/RxD1), though these pins must be reserved and not used for application I/O during debug sessions. The MCU implements Renesas' standard on-chip debugger interface compatible with E8/E8a emulators. Debug functionality requires proper MODE pin configuration and is documented in the R8C/10 Group hardware manual. The R5F21102FP does not include SWD or JTAG interfaces.

Can the R5F21102FP's ADC operate without an external reference voltage?

Yes, the R5F21102FP's 10-bit ADC uses an internal reference derived from VCC when the VREF pin is connected to VCC, as specified in the pin description table. This eliminates the need for an external reference IC in most applications. The ADC maintains linearity and accuracy across the full 0–VCC input range under this configuration, and no external capacitor is required on VREF. The R5F21102FP does not support external reference voltages below VCC.

What are the power supply requirements for the analog section of the R5F21102FP?

The R5F21102FP requires separate analog power connections: AVcc must be connected to Vcc and AVss to Vss, with a 0.1 µF decoupling capacitor between them. IVcc (internal regulator supply) must be connected to Vss via a 0.1 µF capacitor and must never be tied to Vcc. These requirements ensure stable ADC performance and low-noise operation. Violating the IVcc connection rule risks malfunction. All supplies must remain within the 2.7–5.5 V range specified for the R5F21102FP.

Is the R5F21102FP pin-compatible with other members of the R8C/10 Group?

Yes, all R8C/10 Group devices-including R5F21102FP, R5F21103FP, R5F21104FP, and their D-versions-share identical PLQP0032GB-A (LQFP-32) pinouts and electrical characteristics. Memory size differences (8/12/16 KB flash) and temperature grades do not affect pin function or placement. Firmware developed for R5F21102FP can be reused on higher-memory variants without hardware changes, provided code size remains within target flash limits. The R5F21102FP is fully interchangeable at the PCB level with other FP-suffixed R8C/10 devices.