Renesas 3-in-1 drive unit solution helps electric vehicles to sail lightly

     Today, electric vehicle drives are transitioning from traditional distributed systems to centralized architectures. In traditional electric vehicle design, key components such as inverters, on-board chargers, and DC/DC converters are often distributed, working independently and connected to each other through complex wiring harnesses. This design approach is not only cumbersome, but also extremely complex to maintain. In this case, X-in-1 technology was applied. X-in-1 technology is a powertrain integration technology ‌ designed to integrate multiple powertrain components into a single system ‌ to improve overall performance and ‌ to reduce volume and weight. ‌

     Based on X-in-1 technology, Renesas is introducing a 3-in-1 electric vehicle unit solution that integrates multiple distributed systems into a single entity, including on-board chargers, traction motor controls, and DC/DC converters. This integration greatly simplifies vehicle assembly while also reducing system costs.

     The solution uses RH850/C1M, a high-end on-board microcontroller for HEV/EV motor control, as the core control. The RH850/C1M's internal rotary transformer/digitizer (RDC2) and Enhanced Motor Control Unit (EMU2) reduce the CPU load and effectively control the motor with only minimal interaction with the CPU. In terms of MCU power supply, the scheme uses RAA270000KFT power management IC. It includes two integrated current mode DC/DC converters, four low-voltage differential linear regulators and two linear trackers to realize a variety of detection and diagnostic functions such as overvoltage and undervoltage detection of regulators.

     In the design of load power conversion, the scheme adopts PFC+LLC architecture, and is equipped with TP65H035G4WS 650V 35mΩ Gallium nitride FET, RBA250N10CHPF-4UA02 MOSFET, ISL28214 operational amplifier and ISL81802 dual channel synchronous step-down controller.

     The ISL81802 is a dual-channel synchronous step-down controller with peak current mode control and phase interleave between the two outputs. Each output is equipped with a voltage regulator, current monitor and average current regulator to provide independent average voltage and current control. An internal phase-locked loop (PLL) oscillator ensures precise frequency Settings from 100 KHZ to 1MHz, and the oscillator can be synchronized with an external clock signal for frequency synchronization and phase interleaving parallel applications.

     In the design of traction inverter, this scheme uses RBA250N10CHPF-4UA02 MOSFET and ISL78434 half-bridge NMOS FET driver. The ISL78434 half-bridge NMOS FET driver has two independent inputs that can be used to control the high and low side drivers respectively, providing separate pull and fill current pins for each gate driver.

     As competition in the electric vehicle market intensifies, the application of X-in-1 technology will become more widespread. In this context, Renesas will continue to respond to market challenges with its deep expertise in microcontrollers (MCUS), power management ics, analog and mixed-signal ics, and connectivity to provide comprehensive technical support and product services to electric vehicle manufacturers.