Renesas Electronics Corporation, a premier supplier of advanced semiconductor solutions, today announced the new RH850/C1x Series of 32-bit microcontrollers (MCUs), designed for motor control in hybrid electric vehicles (HEVs) and electric vehicles (EVs).
Based on Renesas Electronics’ 40-nanometer (nm) process, the RH850/C1x Series features the RH850/C1H and RH850/C1M MCUs, which enable embedded designers to enhance efficiency, reduce system costs, and achieve higher safety levels for HEV/EV motor control systems.
“Awareness of the vehicle’s environmental footprint is increasing, and HEV/EV designers are seeking ways to deliver even better performance, which requires new and more precise motor control systems,” said Amrit Vivekanand, vice president of automotive, Renesas Electronics America Inc. “The Renesas RH850/C1x MCU series integrates large flash memory capacity, robust motor control peripherals, and single/dual motor control options needed to support the required fine-grained motor control and functional safety for next-generation HEVs and EVs.”
The new RH850/C1x devices can be used with the RAA270000KFT RH850 Family power supply management IC (PMIC), which is currently available in sample quantities. The power management IC integrates into one device all the power supply systems required for MCU operation, two external sensor power supply tracks, and a full complement of monitoring and diagnostic functions, significantly reducing the user burden associated with power supply system design.
Concerns about global warming and regulatory efforts to reduce automotive CO2 emissions are driving demand for new technologies to achieve higher efficiencies. For instance, the Corporate Average Fuel Economy (CAFE) standards are driving OEMS to increase overall fleet miles per gallon (MPG) to 54.5 MPG for cars and light-duty trucks by model-year 2025. As HEV/EV implementations become more mainstream, higher performance applications will require MCUs with greater processing capabilities for efficient motor control. As the HEV/EV market expands, system designers are challenged to reduce costs and increase performance. By integrating hardware peripherals, dedicated for motor control, into the MCU, designers can reduce overall system costs and meet performance requirements.
HEV/EV systems are now being designed to meet ISO 26262 functional safety standards. This system requirement is driving semiconductor products to incorporate a number of embedded features that allow system designers to meet their safety goals.
Key Features of the RH850/C1H and RH850/C1M MCUs:
(1) Incorporation of large memory capacities achieved through 40 nm MONOS process technology
In addition to the use of its leading-edge 40nm process, the RH850/C1x Series is based on Renesas Electronics’ MONOS (Metal Oxide Nitride Oxide Silicon) embedded flash, which has an extensive track record in mass production. The MONOS characteristics include fast readout, low power consumption, and large storage capacity. The RH850/C1M and RH850/C1H devices offer memory capacities of 2 MB and 4 MB, respectively. In addition, 32 KB data flash memory, with essentially the same functionality as EEPROM (electrically erasable and programmable read-only memory), is included for data storage.
(2) Extensive set of peripheral functions for HEV/EV motor control
To improve motor control performance, Renesas is continuing its collaboration with Tamagawa Seiki Co., Ltd., a market leader in R/D converter ICs, and is adopting the technology from that company's new R/D converter IC product, the AU6805, to incorporate R/D converter1 (RDC) functionality into the new RH850/C1x MCUs. Furthermore, the RH850/C1x Series combines the motor control IP core EMU2 (enhanced motor control unit 22) and the TSG3 (Timer S Generation 3). This allows the RH850/C1x MCUs to implement three types of motor control in hardware: sine wave PWM, overmodulation, and square wave. Switching between these three types of motor control according to the conditions allows for highly efficient control, enabling the MCUs to achieve faster and higher performance motor control without imposing a load on the software.
(3) Single motor control and dual motor control support, which can be selected according to the application structure
To support users' diverse HEV/EV system structures, Renesas provides two product types: the RH850/C1M, which incorporates a single R/D Converter, for single motor control and the RH850/C1H, which incorporates a two R/D Converters, for dual motor control. In particular, the RH850/C1H not only provides peripheral functions that can process two systems of motor control independently, but also includes a performance CPU to strengthen software processing capabilities. These devices make it possible to not only implement integrated vehicle control, but also energy management control, DC/DC converter control, battery control and other functions, and other ECU functions.
(4) Diverse set of safety functions for functional safety (ISO 26262) support
Supporting functional safety standards is becoming mission critical due to the increasing amount of electric and electronic equipment used in contemporary cars, and the RH850/C1x MCUs contribute to assuring system safety in end products. The MCUs adopt the lockstep method3 for the main CPU and support data error detection and correction by providing ECC (error checking and correction4) functions for each memory system, such as the flash memory. The MCUs include an ECM (error control module5), to manage error handling. A diagnostic function has also been added to the MCUs’ built-in R/D converter (RDC2) to allow better detection compared with using an external RDC. While diagnostics similar to an external RDC are available, the integrated approach allows designers to quickly and efficiently detect improper operation and limit false negative feedback indications.
In addition to the extensive set of diagnostic functions in these new MCUs and core diagnostic software, Renesas supports user implementation of functional safety by using a watchdog, power supply monitoring, and reset generation functions of the RAA270000KFT PMIC products and providing kits that include these new ICs.
In addition to new product developments, Renesas also intends to provide solutions based on collaborations with partner companies to support user system development including a wide range of software in addition to development environment tools such as debuggers, compilers, model-based development tools, simulators, and RAM monitors.
1 R/D converter: A function that calculates the motor rotation axis angle using analog signals of the resolver sensors.
2 EMU2 (Enhanced Motor Control Unit 2): A hardware unit that performs motor control calculations based on motor current inputs, motor rotation angle inputs, and the command value, and outputs the results through a motor control timer.
3 Lockstep method: A method in which exactly the same processing is performed on two processors and any discrepancies are detected.
4 ECC (Error Checking and Correction): Checks for incorrect values stored in memory and corrects those to correct values.
5 ECM (Error Control Module) : A module that generates interrupts and internal reset signals from a variety of error sources and monitor circuits.
Pricing and Availability
Samples of the RH850/C1H and RH850/C1M MCUs are scheduled to be available from the beginning of CY2015, priced at US$ 45 and US$50 per unit, respectively. Mass production is scheduled to begin in May 2016 and is expected to reach a scale of 100,000 units per month. (Pricing and availability are subject to change without notice.)
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