Renesas Electronics Introduces the New RL78 Microcontroller Family for Next-Generation 8-/16-bit Embedded Applications

Renesas Electronics Corp. announced the introduction of the new RL78 family of extremely low power microcontrollers (MCUs). The RL78 integrates advanced features from both the R8C and the 78K (78K0, 78K0R) families to deliver lower power, enhanced performance, and higher integration, providing a robust migration path. The new products are built around the company’s new RL78 CPU core, which is based on the low-power, high-performance 78K0R CPU core, and incorporates an extensive range of powerful peripheral functions from the R8C and 78K families, making them well suited for a number of applications including battery-operated devices and household applications.

The new RL78 MCUs achieve industry-leading low power consumption, with operating current of only 70µA)/MHz and standby current of 0.7 µA with the real-time clock (RTC) and low-voltage detection (LVD) functions active. The new family’s power-efficient design, based on a 130-nanometer (nm) process node, can deliver 41 Dhrystone million instructions per second (DMIPS) when operating at 32 MHz. The new RL78 MCUs’ advanced process technology enables higher integration of on-chip components such as a 32MHz ±1 percent on-chip oscillator, data flash with background operation supporting up to one million rewrite cycles, and 1.6 to 5.5V operation. These features provide greater functionality while reducing overall system cost, which are vital requirements for next-generation 8-bit designs.

The RL78 family will be comprised of both general-purpose and application-specific standard MCUs. The general-purpose "G" series will include a total of 302 products in the RL78/G12 Group and RL78/G13 Group. The initial products will offer extensive scalability with 2 kilobytes (KB) to 512 KB of program space and with package options ranging from 20 to 128 pins.

Renesas Electronics was formed on April 1 through the merger of NEC Electronics Corporation and Renesas Technology Corp. Since then the company has boosted product development efficiency by adopting (integrated) platforms as the basis of design work in its key MCU business. The number of processes used is also being reduced from six to three as the company builds a fab network that will help reduce production costs and strengthen its ability to respond to shifting demand trends.

The RL78 MCUs are the first family of MCUs to be developed using an integrated platform following the merger and to employ the new 130 nm process. The RL78 Family combines and extends technology from the earlier R8C and 78K 8-bit and 16-bit MCUs from the two merged companies, contributes to lower overall system power consumption, provides an extensive variety of different product versions, and will help developers reduce overall system costs. The RL78 Family was developed to meet future requirements of the 8-bit and 16-bit MCU market for the foreseeable future.

In addition to its 70µA/MHz current consumption in active mode, and 0.7µA with RTC plus LVD active, the RL78 MCUs support a new low-power mode called "Snooze Mode." This mode supports A/D conversion and serial communication while the CPU is in standby mode, which can significantly extend the life of battery-operated devices.

The RL78 MCUs incorporate a number of built-in mechanisms that can be utilized to comply with standard safety regulations (such as IEC60730) that are required for electrical appliances. Such features include a flash memory cyclic redundancy check (CRC) function, RAM parity error checking, clock fail and frequency detection circuit, A/D test function and illegal memory access detection.

Available hardware development tools include Renesas Electronics’ low-cost E1 on-chip debugging emulator and the IECUBE full-spec emulator, which provide customers with the ability to choose the MCU product that best matches their debugging requirements. Plans call for the release of versions of the E1 emulator for all Renesas Electronics’ MCUs in addition to the RL78 Family, providing broad support for Renesas Electronics products at low cost.

Samples of Renesas Electronics’ new RL78 MCUs will be available in Q1. Mass production is scheduled to begin in July 2011 and is expected to reach a combined volume of 10 million units per month in 2012. Pricing will differ according to memory capacity, package type, and pin count. As an example, the RL78/G12 Group MCUs with 2 KB of flash memory and 256 bytes (B) of RAM in a 20-pin shrink small-outline package (SSOP) will be priced at $0.45 per unit in 10,000-piece lots, and the RL78/G13 Group MCUs with 64 KB of flash memory and 4 KB of RAM in a 64-pin, low-profile quad flat package (LQFP) will be priced at $1.00 per unit in 10,000-piece lots.