Renesas R5F10366ASP#V0

Overview

R5F10366ASP#V0 from Renesas Electronics is a 20-pin LSSOP ultra-low-power 16-bit RL78/G12 microcontroller targeting cost-sensitive consumer applications. It features 2 KB code flash, 256 B RAM, 1.8–5.5 V operation, 24 MHz max CPU speed (31 DMIPS), and operates across –40°C to +85°C. It integrates an 8/10-bit 11-channel ADC, UART, simplified SPI (CSI), watchdog timer, and low-power HALT/STOP/SNOOZE modes-ideal for battery-powered sensor nodes and smart home peripherals.

For engineers reviewing the R5F10366ASP#V0 datasheet, R5F10366ASP#V0 pinout, R5F10366ASP#V0 application, or R5F10366ASP#V0 equivalent, key selection criteria include its 20-pin LSSOP-20 package, absence of data flash memory, single UART channel, no DMA or CRC engine, and ±5.0% high-speed on-chip oscillator accuracy over –40°C to +85°C-critical for timing-critical but non-safety-critical embedded control.

Technical Context

The R5F10366ASP#V0 implements the RL78 CPU core with CISC architecture and 3-stage pipeline, delivering 0.04167 µs minimum instruction execution time at 24 MHz using the high-speed on-chip oscillator. Its peripheral set is trimmed relative to R5F102 variants: it omits data flash, DMA, CRC, RAM guard, and SFR guard, and supports only one UART channel and one simplified SPI (CSI) channel-reflecting its role as a streamlined, entry-level MCU for basic I/O and serial communication tasks.

Power management centers on three low-power modes (HALT, STOP, SNOOZE) enabled by the on-chip power-on-reset (POR) and voltage detector (LVD) with 12 selectable threshold levels. The 15 kHz low-speed on-chip oscillator provides clock source for watchdog and interval timer during deep sleep, while the main system clock supports crystal (1–20 MHz) or internal oscillator (1–24 MHz) sources-enabling flexible trade-offs between precision, power, and BOM cost.

Key Specifications

Pinout & Package

Package: 20-pin plastic LSSOP (4.4 × 6.5 mm, 0.65-mm pitch), RoHS-compliant, tray packaging (#V0).

Key Features

Applications

Equivalent & Alternatives

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

Compared with R5F10366ASP#V0, the R5F10266ASP#V0 adds data flash and safety features at higher cost and power, while R5F10368ASP#V0 scales memory upward within the same low-feature, low-cost envelope-making both viable alternatives depending on whether functional expansion or memory headroom is the priority.

Availability

R5F10366ASP#V0 is available at Aetrix Electronics and suitable for smart home sensors, wireless transmitters, USB-C monitors, and industrial indicators requiring stable component supply, long-term manufacturability, and Renesas' industrial-grade qualification.

Supply support for R5F10366ASP#V0 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 Japanese semiconductor manufacturer specializing in microcontrollers, analog, power, and SoC solutions for automotive, industrial, and IoT markets.

The RL78/G12 product line delivers ultra-low-power 16-bit MCUs optimized for cost-sensitive, battery-operated consumer and industrial control applications-emphasizing energy efficiency, integrated analog, and simplified development.

FAQ

What is the maximum operating frequency and corresponding performance of the R5F10366ASP#V0?

The R5F10366ASP#V0 achieves a maximum operating frequency of 24 MHz using its high-speed on-chip oscillator, delivering 31 DMIPS of processing performance. This speed is validated across its full 1.8–5.5 V supply range and –40°C to +85°C temperature range. Its minimum instruction execution time is 0.04167 µs under these conditions, enabling responsive real-time control in timing-critical applications such as motor commutation or sensor sampling.

Does the R5F10366ASP#V0 include data flash memory, and what are the implications for firmware updates?

No, the R5F10366ASP#V0 does not include data flash memory-this is a defining distinction from the R5F102xx series. As confirmed in the RL78/G12 datasheet Section 1.3.1, R5F103 products omit the 2 KB data flash block. Consequently, field firmware updates requiring non-volatile parameter storage or background reprogramming must rely on external EEPROM or utilize code flash sectors with careful wear-leveling-increasing design complexity compared to R5F10266ASP#V0.

What serial communication interfaces are supported by the R5F10366ASP#V0, and how many channels are available?

The R5F10366ASP#V0 supports one UART channel, one simplified SPI (CSI) channel, and zero simplified I²C channels-as explicitly defined in Table 1-1 and Section 1.7 of the RL78/G12 datasheet. Unlike R5F1026x variants, it lacks dual CSI and dual simplified I²C. This makes it suitable for point-to-point serial communication (e.g., UART to RF IC or CSI to display driver) but not for multi-drop I²C sensor networks without external bridging.

What are the low-power capabilities of the R5F10366ASP#V0, and how do they compare to competing MCUs?

The R5F10366ASP#V0 offers three hardware-supported low-power modes: HALT (CPU stopped, peripherals active), STOP (all clocks halted, <0.5 µA typical), and SNOOZE (selective peripheral operation with wake-up capability). Its active current is rated at 63 μA/MHz-among the lowest in its class for 16-bit MCUs. These features enable multi-year battery life in coin-cell applications, outperforming many 8-bit alternatives in µA/MHz efficiency while retaining 16-bit addressing and richer peripheral integration.

Is the R5F10366ASP#V0 pin-compatible with other RL78/G12 20-pin variants, and what design considerations apply?

Yes, the R5F10366ASP#V0 is pin-compatible with all RL78/G12 20-pin LSSOP variants (e.g., R5F10266ASP#V0, R5F10368ASP#V0) sharing the PLSP0020JB-A package. However, functional differences exist: R5F10366ASP#V0 lacks data flash, DMA, and CRC, and has reduced oscillator accuracy (±5.0% vs. ±1.0%). PCB layouts can be reused, but firmware must account for missing peripherals and adjusted timing margins-especially in UART baud rate calculations and watchdog timeout settings.