The successors to the 78K0R and R8C, with the industry's lowest level of consumption current. Automotive general-purpose low-end microcontrollers with various built-in functions necessary for automotive application communications and implementing functional safety.


RL78/F12 microcontrollers are available in a 20 to 64-pin, 8 to 64 KB flash memory lineup, and realize the industry's lowest level of consumption current. They have a built-in LIN module as an automotive interface. With various built-in functions for realizing functional safety including flash memory CRC calculation, illegal memory access detection, RAM guard, A/D converter testing, and SFR guard, a highly reliable system can be built, so these microcontrollers can be used for industrial applications and of course automotive applications.


Product Status: Mass Production
Family: RL78
Series: RL78/F1x
Group: RL78/F12


RL78/F12 Block Diagram


Pin Count
Package Type
Program memory
32 KB Flash memory
2 KB
Data Flash
4 KB
CPU (Bit, Clock, DMA, External Bus etc)
RL78 (16-bit)
Max. Frequency
32 MHz
Sub-Clock (32.768 kHz)
On-chip Oscillator Freq.
32M, 24M, 16M, 12M, 8M, 4M, 1M Low-speed Oscillator 15kHz
Real-Time Clock (RTC)
Power-On Reset
Low Voltage Detection
DMA Remarks
DMAC x 2 ch
External Interrupt Pins
I/O Ports
16-bit Timers
8 ch
Watchdog Timers
1 ch
Other Timers
Interval Timer x 1 ch, Wakeup Timer x 1ch
PWM Output
A/D Converters
10-bit x 10 ch
6 ch
5 ch
5 ch
2 ch
Operating Conditions
Operating Voltage
2.7 to 5.5 V
Power Supply
Operating Temperature
-40 to 125 ℃ (Ambient Temperature)

You can find an explanation of orderable part numbers here.


Resources for Software and Hardware

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e-learning Information for studying and learning about microcontrollers and microprocessors.
FAQ Frequently asked questions and useful hints for development.
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Software Design Support

Title Description
e² studio This integrated development environment (IDE) is based on the popular combination of the open-source Eclipse IDE and its CDT plug-in that enables C/C++ language development.
CS+ This integrated development environment (IDE) can be used for coding, assembly, compiling, and simulation. CS+ is also included with starter kits.
E2 emulator Lite This entry-level on-chip debugging emulator provides functionality equivalent to that of the E1 emulator at a low price.
E2 emulator This on-chip debugging emulator has advanced features that improve the efficiency of development. In addition to the basic functions from debugging to flash programming, this emulator supports hot plug-in and external triggers as standard items. This emulator also helps to reduce development time by downloading at high speeds (compared to the E1 emulator) and the ability to work in combination with various solutions such as the tuning of current drawn by systems under development.
E1 emulator This on-chip debugging emulator is a standard model which provides basic debugging functions (production is to be discontinued at the end of December 2019).
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