ROHM Semiconductor – ML610Q793 and ML610Q794G: The Industry’s Smallest Low Power Microcontrollers for Sensor Management



The ML610Q793 and ML610Q794G 8bit MCUs are specifically designed to manage, collect, and analyze data from an array of environmental sensors.  

They integrate a proprietary high-performance 8-bit RISC CPU core (U8) and 16-bit coprocessor for arithmetic operations, along with analog to digital converters and multiple interfaces in an ultra-compact form factor.

These devices operate at up to 4MHz (4MIPS) and include 64Kbytes of FLASH for program storage, 4Kbytes of RAM for program use, and 8Kbytes of Dual Port RAM for data logging. The on-chip coprocessor can perform Multiplication, Division, and Square Root functions, allowing for advanced data analysis. In addition, a variety of interfaces are provided that allow connection to virtually any type of sensor. For analog output sensors there are 3 channels of 12bit Successive Approximation Analog to Digital Conversion (SA-ADC), and for interfacing with digital sensors and wired/wireless communication devices four ports are included: SPI Master, I2C Master, UART, and Synchronous I/O. General Purpose I/O and an I2C Slave I/F for interfacing to a host processor are also available.

ML610Q79x devices can be used as a pre-processor to a more powerful host processor or as a main processor in a variety of designs. Their robust processing capabilities and low power (0.6uA at Halt, less than 1mA at full speed) operation make them ideal for Internet of Things (IoT) applications requiring data collection and processing with minimal power consumption.

The ML610Q793 is offered in a thin, compact 48pin WL-CSP (Wafer Level-Chip Scale Package) measuring just 3.1mm x 3.0mm, while the ML610Q794G, which features all of the functions of the ML610Q793 and includes an IrDA interface, is available in a 48pin QFP package.

Typical System Block Diagram

Typical System Block Diagram



  • Internet of Things (IoT) applications
  • Home and building automation
  • Smartphones
  • Sensor network modules
  • Wearable health & fitness devices

Key Features

  • Designed to control multiple sensors with low power consumption
  • 8-bit RISC CPU (U8) core and 16-bit arithmetic coprocessor operate at 4MHz and provide independent sensor control and management without host CPU
  • Multiple interfaces enable broad compatibility (I2C Master/Slave, SPI, GPIO, UART)
  • 12-bit high-performance ADC
  • On-chip memory for program storage and data logging


Part NumberML610Q793ML610Q794G
CPU Core8-bit RISC CPU nX-U8 / 100 Core8-bit RISC CPU nX-U8 / 100 Core
ROM (Flash)64KB*64KB*
RAM (Logging RAM)8KB8KB
A/D Converter12-bit Successive Approximation Type x 312-bit Successive Approximation Type x 2
Operating Freqency: High Speed4.096MHz (Built-in PLL)4.096MHz (Built-in PLL)
Operating Freqency: Low Speed32.768kHz (External clock)32.768kHz (External X'tal)
Operating Voltage: Interface1.7V to 1.9V2.5V to 3.6V
Operating Voltage: A/D Converter2.5V to 3.6V2.5V to 3.6V
Supply Current (Typ.): Standby modeHALT mode : 0.6μAHALT mode : 0.7μA (T.B.D.)
Supply Current (Typ.): Operating Mode32.768 kHz : 7.5μA32.768 kHz : 7.5μA (T.B.D.)
Supply Current (Typ.): Operating Mode4.096MHz : 930μA4.096MHz : 1000μA (T.B.D.)
Form FactorWCSP48TQFP48
Software Development Kit (SDK)
  • Sensor drivers/Firmware
  • Pedometer, activity detection, calorie calculation
  • Sensor drivers/Firmware
  • Pedometer, activity detection, calorie calculation

*Contains a test area of 1Kb