True Low Power

The RL78 microcontrollers (MCUs) offer three low power modes that maximize battery life by disabling idle CPU features.

RL78 True Low Power Diagram

SNOOZE mode sequencer (as of 2023, only RL78/G23, G22 have this function)

This function makes it so that you do not need to wake up the CPU for receiving data. The unique SNOOZE mode allows some peripherals, i.e., ADC and UART, to operate while in standby modes. The RL78/G23 and RL78/G22 have the SNOOZE mode sequencer, which can operate most peripheral functions while in SNOOZE mode. The SNOOZE mode sequencer realizes even lower power consumption for applications.

Standby Modes

The RL78 MCUs include HALT and STOP modes

  • HALT mode disables CPU operation saving as much as 80% of total MCU current, whilst allowing fast CPU enable time
  • STOP mode achieves lowest power consumption by disabling more CPU functions

Power Consumption Values


Broad Scalability

RL78 MCUs Offer an Unprecedented Lineup

  • Over 1000 devices
  • Available in 8- to 144-pin packages and 1KB to 768KB Flash
RL78 MCUs are available in 8- to 144-pin packages and 1KB to 768KB Flash

Excellent pin compatibility

  • Scalability is maintained because the general location of peripheral function pins and input/output pins remains the same even when the pin count changes. Customers can continue to use the RL78 Family of microcontrollers with confidence in the future.
  • Customers can use standardized boards for product models ranging from the low-end to the high-end and boost the efficiency of the verification process.
Example of I/O port assignments on RL78/G1x

Peripheral I/O Re-direction (PIOR) capability remaps functions to alternate ports

  • Due to layout or peripheral pin sharing constraint, there may be conflicts for existing peripheral I/O pin assignments
  • Optimize peripheral pin functionality by easing function bottlenecks on a pin

RL78 Peripheral I/O Re-direction (PIOR) Capability

RL78 Peripheral I/O Re-Direction (PIOR) Capability

High Performance

RL78 microcontrollers with CPU core employing three-stage pipeline and Harvard architecture

RL78 CPU processing performance is overwhelming other MCU vendors' CPU cores.

  • 16-bit CPU Core with Pipelining
  • Efficient Instruction Execution -> 86% in 1-2 Cycles
  • Single Cycle Multiplication (HW Math Assist)
  • DMA Engine (up to 4 channels)
RL78 Instruction Execution Cycles
HW Assist for Math Operation Clock Cycles
16bit Barrel Shifter for Shift and Rotate 16bit n Shift/Rotate (n = 1 to 15) 1
Multiply Signed & Unsigned 16 × 16 = 32 Bit Result 1
Multiply/Accumulate Signed & Unsigned 16 × 16 + 32 = 32 Bit Result 2

System Cost Reduction

Microcomputer Built-in Functions

  • Reset circuit
  • Low power detection circuit
  • Watchdog timer
  • High-precision (1%) on-chip oscillator
  • Data flash memory
  • Temperature sensor
  • Multi power supply interface port

RL78 Built-in Peripherals

RL78 Built-in Peripherals

High Quality and Safety

Hardware for IEC/UL 60730 Compliance

RL78 Quality and Safety

RL78 Quality and Safety

Comprehensive Development Tools

Hardware Development Tools

A low-cost on-chip debugging emulator and a full-spec emulator are available. You can select the environment that best matches your debugging needs.

E2 and E2 Lite On-chip Debugging Emulator

The E1 emulator provides a wide range of support for Renesas microcontrollers at low cost.

Learn more about the E2 Emulator, E2 Lite Emulator

IECUBE In-circuit Emulators

Comprehensive break functions, trace functions useful for analyzing illegal operations, time measurement functions for measuring maximum/minimum/average program execution times, coverage functions for measuring program execution coverage rate, and more, are equipped as standards.

Learn more about IECUBE for the RL78 Family

Various evaluation boards

Fast Prototyping Board、Renesas Starter Kit、CPU Board etc.

Learn more about RL78 Family Development Environment

Software Development Tools

The CS+ integrated development environment (IDE) with a track record of "easy operation and easy support", a real-time OS compliant with the μITRON specification, and the PG-FP6 flash programmer, and Smart Configurator are available. We provide strong support for application development.

Learn more about the CS+ IDE
Learn more about the PG-FP5 Flash Programmer

RL78 Software Development, Debugging and Programming

RL78 Software Development, Debugging and Programming