Renesas Technology to Release SH74552 and SH74562 MCUs with On-Chip Flash Memory and Compact Package for Applications of Advanced Driver Assistance Systems

The specifications of the SH74552 and SH74562 have been carefully selected for systems intended for mid and low range vehicles. By integrating in a compact package the capability for high-speed and fine-grained processing of large amounts of data from sensors, they make it possible to build systems that are more compact and lower in cost.

Renesas Technology’s SH7450 Series MCUs for applications of advanced driver assistance combine on-chip flash memory and high-speed operation. Sample shipments of products with a high operating frequency of 240 MHz have already begun to manufacturers of luxury cars. In recent years, in response to rising market consciousness about safety, demand has grown for advanced driver assistance suitable not only for high-end vehicles but for popularly priced vehicles such as eco-friendly cars and compact cars as well. The new SH74552 and SH74562 retain the high performance and special characteristics of the earlier products in the SH7450 Series and provide a carefully selected function set in a package with a mounting area that is 42% smaller.

The SH74552 and SH74562 employ a FBGA package measuring only 13 mm × 13 mm, deliver the high-speed operation and large-capacity memory necessary for high-speed and fine-grained processing of large volumes of data from sensors in applications such as obstacle detection and risk avoidance, and integrate on-chip peripheral functions such as CAN. They are based on Renesas Technology’s existing 240 MHz products (17 mm × 17 mm) and provide a carefully selected subset of their specifications. This makes it possible to build advanced driver assistance systems that require less space, are lower in cost, and are more lightweight, making them suitable for popularly priced vehicles.

Both devices deliver high-speed operation, with processing performance of 288 MIPS (million instructions per second) at the maximum operating frequency of 160 MHz. This enables them to process large volumes of data from sensors, cameras or radar, very rapidly. In addition, since these lower-end MCUs are based on the 240 MHz products that preceded them, existing software resources can be reused, making it possible to quickly develop advanced driver assistance systems for popularly priced vehicles by adapting systems originally intended for luxury cars.

The SH74552 and SH74562 have an ample 1 MB of on-chip flash memory to accommodate the large software programs required by advanced driver assistance systems. Renesas Technology MCUs with on-chip flash memory have a proven track record in a wide range of fields, including automotive, consumer, and industrial equipment, and are highly regarded for their excellent reliability and high-speed operation. The SH74552 and SH74562 also have 256 KB of on-chip SRAM for storing large amounts of data such as radar data or image data from cameras.

In an advanced driver assistance system, data detected by a sensor electronic control unit (ECU) linked to milliwave radar, cameras, etc., is transferred via a controller area network (CAN) to a sensor fusion ECU, which uses it to perform control functions. The SH74552 and SH74562 integrate 4-channel CAN functionality to accommodate additional sensor or actuator ECUs for higher-performance advanced driver assistance systems.

Going forward, the amount of communication data handled is expected to increase rapidly to support coordinated control among vehicle systems, and it is possible that the communication speed of the present CAN specification may prove inadequate. For this reason, the SH74552 is equipped with a 2-channel FlexRay controller, a next-generation backbone network specification providing faster communication speed and enhanced reliability.

In addition to the CPU core, the SH74552 and SH74562 also incorporate a floating-point processing unit (FPU) operating at 160 MHz. The FPU supports both single-precision and double-precision calculations, and in single-precision operations it achieves a maximum performance of 1.12 GFLOPS (giga [billion] floating-point operations per second). Hardware support for vector operations and arithmetic operations such as sine/cosine operations enables high-speed operation processing. The SH74552 and SH74562 also have a wide operating temperature range (–40 to +125°C) to accommodate the wide temperature range under which advanced driver assistance systems must operate. Finally, they incorporate a careful selection of the on-chip peripheral functions of the first two products in the SH7450 Series, including those needed for controlling vehicle cameras and for vehicle milliwave systems.

Camera interface functions required by lane departure warning systems detect the white lines on the road surface and issue warnings when a vehicle deviates from its lane. For image data captured by CMOS cameras, the SH74552 and SH74562 incorporate two clock synchronous parallel interface direct RAM inputs (DRIs) that are connected directly to the on-chip SRAM and support a maximum data transfer speed of 40 MB per second. In addition to a function for reading in an entire image at once, there are built-in functions for selectively reading in only necessary pixels and for reading in images with a reduced pixel count. This allows more efficient utilization of the on-chip RAM and helps boost operation efficiency. A single-channel I2C function required for camera settings is also provided. This makes it possible to design systems that are more compact and less costly.

Functions required by milliwave radar systems, such as adaptive cruise control systems, detect obstacles and pedestrians in front of the vehicle, automatically track leading vehicles, and perform emergency braking, etc. Both devices include a parallel DAC controller (PDAC) circuit for D/A converter control on-chip, as well as a parallel selector (PSEL) circuit for channel control of external high-speed A/D converters (ADCs), a DRI circuit ideal for reading in data from external high-speed ADCs, and a timer TOU for controlling a brushless DC motor (BLDC) as part of mechanical milliwave scan control and 62-channel ATU-IIIS (Advanced Timer Unit III) multifunction timer unit ideal for timing control. These on-chip functions make it possible to build systems that are more compact and lower in cost.