The reference design uses a modular approach in both hardware and software to showcase core and optional functional blocks that can be adopted for many 24V-48V applications such as lawn mowers, electric carts, robot cleaners, power tools, and power banks.
It uses 15 Renesas ICs, including three key devices: the ISL94216 16-cell battery front end (BFE), robust HIP2211 100V MOSFET drivers, and RX23T 32-bit microcontroller (MCU) for motor control. The 48V mobility solution is powered from a 25 AHr Li-ion battery that drives a 1600W inverter to attain speeds of up to 5000 rpm.
“Micromobility options like e-scooters and e-bikes offer an attractive, low-carbon footprint vehicle for first-mile and last-mile travel. Rising demand for these applications is driving new battery management capabilities as cell balancing plays an increasingly critical role in recharging,” said DK Singh, Director, Systems and Solutions Team at Renesas . “Our 48V mobility winning combination solution combines Renesas’ advanced BFE, industry-leading MCUs, along with analogue and power devices, and innovative motor control technology to help customers speed up the development of their high power and torque e-scooters and e-bikes.”
The 48V mobility winning combination solution includes two boards that address the higher battery cell count and power levels mobility applications require. The BFE and charger board focuses on larger, higher voltage battery packs. The motor control and inverter board features synchronised current/voltage measurements and drivers that are pulse width modulated (PWM) to actuate the motor, and monitor motor status. The algorithm with the hardware is ideal for driving brushless DC (BLDC) motors. Also, two optional boards are available: the wireless charging receiver board, and the Bluetooth® Low Energy (BLE 5.0) control board.
For system control, the solution uses a cost optimised, energy-efficient RX23T MCU with built-in floating point unit (FPU) and six high-performance timers specifically tooled for complex inverter control algorithms.
These specific features and modular design will help engineers reduce the man-hours in software/hardware development and debug. In addition, unlike other large cell count single-chip battery managers, the highly integrated ISL94216 offers several features that balance and monitor system conditions to improve battery life and safety, independent of the MCU. The winning combination solution also uses the ISL81601 60V bidirectional 4-switch synchronous buck-boost controller for ultra-fast charging. The controller’s CC/CV charger profile is implemented through the system MCU.
