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Compact, low power, high function general-purpose microcontrollers ideal for sub-microcontrollers


RL78/G12 microcontrollers balance the industry's lowest level of consumption current (CPU: 63 μA/MHz, standby (STOP): 230 nA) and a high performance of 30 DMIPS (24 MHz). They have an on-chip oscillator, data flash, A/D converter, and more. Built-in safety features (function that detects illegal operation of hardware) enable support for the household appliance safety standard (IEC/UL 60730). With a 20 to 30-pin compact package lineup, these microcontrollers are perfect for sub-microcontrollers of small appliances and consumer and industrial equipment.


Key Features:

Pin Count
20 pins 24 pins 30 pins
CPU Core RL78 core
Prpgram Flash (KB) 2 to 16 4 to 16  
Data Flash (KB) 2
SRAM (B)  256 to 1.5 KB 512 to 1.5 KB
Main System Clock High-speed system clock(fMX) X1 (crystal/ceramic) oscillation, external main system clock input (EXCLK): 1 to 20 MHz (VDD = 2.7 to 5.5 V), 1 to 8 MHz (VDD = 1.8 to 5.5 V)
High-speed on-chip oscillator clock (fIH) 1 to 24 MHz (VDD = 2.7 to 5.5 V), 1 to 16 MHz (VDD = 2.4 to 5.5 V), 1 to 8 MHz (VDD = 1.8 to 5.5 V)
Low-speed on-chip oscillator clock   15 kHz (VDD = 1.8 to 5.5 V
I/O port Total 18 22 26
CMOS I/O 12 (N-ch O.D. output: 4) 16 (N-ch O.D. output: 5) 21 (N-ch O.D. output: 9)
CMOS input 4 5 9
N-ch open drain I/O (6 V tolerance) 2
Timer 16-bit (TAU) 4 8
12-bit interval timer 1
Watchdog timer 1
Timer output 4(PWM output:3) 8(PWM output:3)
Serial Interface CSI:1 ch/
UART:1 ch
0 to 1 Unit
CSI:2 ch/simplified I²C:2 ch/UART:1 ch 0 to 1 Unit -
CSI:1 ch/simplified I2C:1 ch/UART:1 ch - 3 Unit
I²C bus 1 channels
8/10-bit resolution A/D converter 11 channels 8 channels
Clock/Buzzer output 1 2
Power-on reset on
DMA 0 to 2 channels
External interrupt pins 10 14 6
Multiplier/divider/multiply-accumulator Multiplication/Division multiply library support (unit operations)
Safety Function RAM parity error detection
Invalid memory access detection
Frequency detection
A/D converter testing
CRC calculation(General purpose)
RAM guarding
SFR guarding
R5F1026x R5F1027x R5F102Ax
On-chip debug on
Power supply voltage VDD=1.8 to 5.5V
Operating ambient temperature TA = - 40 to + 85 ℃ (A-version for consumer applications and D-version for industrial applications)
TA = - 40 to + 105 ℃(G-version for industrial applications)

※ When I use data flash, an exclusive library (approximately 8.1 K byte) is necessary.


Pin Count / Memory Size Lineup:

RL78/G12-Pin Count/Memory Size


Block Diagram:

RL78/G12 Block Diagram

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Hardware Design Support

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Characteristics data Information on observed values. Please use this as reference data when developing your set.
Oscillation circuit characteristics The resonators for which the operation is verified and their oscillator constants are shown below.
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