RAJ240310 is Renesas Li-ion battery fuel gauge IC (FGIC) which consists of a MCU device and an AFE device in a single package. Packed with a variety of battery management features and a Renesas RL78 CPU core which has multiple low power modes, and achieves a high performance under ultra-low power operation. RAJ240310 has embedded flash memory on an MCU (same as other RL78 family) and use it to store program instructions (code) as well as data on to perform battery voltage / current / temperature measurement, remaining capacity estimation, over current / voltage / temperature protection and other battery management operations.


  • Fully integrated battery management solution with battery capacity  measurement and programmable protection capability.
  • Supports 3-10 series Li-ion or Li-Polymer battery cells
  • Integrated with Renesas Ultra Low Power RL78 CPU core for multi-function process
  • Memory: Code flash memory: 64KB, Data flash memory (up to 100,000 erase/write cycles): 4 KB, SRAM : 4 KB
  • Clock generator: High-Speed on-chip oscillator: up to 32 MHz, Low speed on-chip oscillator: 15 KHz, AFE on-chip oscillator: 4.19MHz, AFE low speed on-chip oscillator: 131.072 KHz
  • General Purpose I/O Ports: Total: 15 pins, CMOS input/output: 6 pins, CMOS input: 2 pins, N-ch open drain input/output [6.5V tolerance]: 2 pins, N-ch open drain input/output [VREG2 tolerance]: 2 pins, High voltage input/output [VCC tolerance]: 3 pins
  • Serial interface: CSI (SPI): 1 channel, I2C: 1 channel, UART: 2 channels, Simplified I2C: 1 channel
  • Timer: MCU 16-bit timer: 5 channels, MCU 12-bit interval timer: 1 channel, AFE timer: 2 channels, (  AFE timer A: setting range: 125 msec to 64 sec, AFE timer B: setting range: 30.52 usec to 2 sec )
  • Embedded A/D converter: AFE 15-bit resolution delta-sigma A/D converter
  • Current measurement circuit: AFE 18-bit resolution delta-sigma A/D converter
  • Battery cell voltage and temperature (AN port voltage) detection circuit: Monitoring over/under voltage and temperature by delta-sigma, A/D converter (AFE) without controlling from MCU
  • Impedance measurement circuit: Simultaneous measurement of battery voltage and current
  • Over current detection circuit: Short circuit: 1 filter, Discharge over current: 4 filters, Charge over current: 1 filter, Charge wakeup: 1 filter, Discharge wakeup: 1 filter
  • Series regulator: 3.3 V output (> 20mA)
  • Charge and Discharge MOSFETs control: Low side N-ch Dual MOSFETs drive circuit embedded, Support individual FET control
  • Low Power mode: 
  • Low Power Mode (< 25uA): RAM Retention, LF Oscillator
  • Power Down Mode (< 2uA)
  • Additional features: Internal Cell Balancing Circuit (>10mA), Internal Watchdog Timer (MCU), MCU Runaway Detection Circuit (AFE), 4 Thermistor Sensor Ports with On-chip Pull-up Resistors, Integrated Hardware Diagnostics function, Load detection circuit, Random cell connection tolerant
  • Voltage and temperature condition
  • Power supply voltage: VCC = 8.0 to 50V, Operating Ambient Temperature: Ta = -40°C to 85°C
  • Package Information: 40pin QFN Package ([Body] 5 mm x 5 mm, 0.4 mm pitch)




Design & Development