Skip to main content



The following page content corresponds to the products marketed in Japan.
If you do not live in Japan, please

Product Overview:

RL78/G12 Group microcontrollers employ the RL78 core which realizes high processing performance while delivering the lowest power consumption in their class, and have an expansive lineup of products with low capacity memory for small home appliances.
A high-precision (±1%) on-chip oscillator makes 24 MHz CPU operation possible, and built-in features such as a reset circuit, a low voltage detection circuit, a watchdog timer, and data flash with background operation function help to lower the total cost of building a system and contribute to more compact size and lower power consumption.
In addition, abundant functions for supporting functional safety, such as an A/D converter testing function, are also on-chip.
With 20, 24, and 30-pin small packages, and a lineup with 2 KB to 16 KB small-capacity flash memory, these products are suitable for use as sub-microcontrollers in small home appliances and general consumer electronic devices.

Pin Count / Memory Size Lineup:


Block Diagram:

Block Diagram image

Key Features:

Operating voltage: VDD = 1.8 to 5.5 V
Max. frequency: 24 MHz
ROM capacities: 2 KB to 16 KB flash memory
RAM capacities: 256 B to 2 KB
Available on-chip data flash (2 KB) products (Product name :R5F1026x, R5F1027x, R5F102Ax)
20-pin plastic SSOP package, 24-pin plastic QFN package, 30-pin plastic SSOP package
General-purpose register: 8 bits x 32 registers (8 bits x 8 registers x 4 banks)
High-speed on-chip oscillation clock

  • 24 MHz high-speed oscillation clock: 24 MHz (TYP.)

On-chip single-power-supply flash memory (with prohibition of chip erase/block erase/writing function)
Self-programming (flash shield window function)
On-chip debug function
On-chip power-on-reset (POR) circuit and voltage detector (LVD)
On-chip watchdog timer (operable with the on-chip internal low-speed oscillation clock)
On-chip multiplier/divider/multiply-accumulator

  • 16 bits x 16 bits = 32 bits(signed)
  • 16 bits x 16 bits = 32 bits(unsigned)
  • 32 bits / 32 bits = 32 bits(unsigned)
  • 16 bitsx 16 bits + 32 bits = 32 bits (signed)
  • 16 bitsx 16 bits + 32 bits = 32 bits (unsigned)

On-chip key interrupt function (R5F26x, R5F27x, R5F36x, R5F37x)
On-chip clock output/buzzer output controller
On-chip BCD adjustment
I/O ports: 16 to 26 (N-ch open drain: 2)

  • 16-bit timer: 4 to 8 channels
  • Watchdog timer: 1 channel
  • Interval timer: 1 channel

Serial interface

  • CSI/UART/Simplified I2C
  • I2C

Stanby function

  • HALT
  • STOP

10-bit resolution A/D converter(VDD = EVDD = 1.8 - 5.5 V): 8 to 11 channels
Operating ambient temperature: TA = -40 to +85°C

Key Applications:

  • Consumer Electronics, Industrial

Product Lineup:


Alliance Partner



End of content

Back To Top