Delivering 1.65DMIPS/MHz CPU performance, integrating no-wait flash memory, and offering enhanced timers and analog functions, these microcontrollers highlight Renesas’ commitment to its ‘Green Energy Initiative’ because they let customers build products that consume less power.
Renesas Technology Inc., announced the release of the RX62T group of microcontrollers (MCU). The new devices have strong eco-features and deliver the environmental performance now in high demand for motor-control and inverter-control applications. These 100MHz, feature-rich MCUs with no-wait flash memory illustrate how Renesas is using the goals of its corporate ‘Green Energy Initiative’ to drive chip design in eco-friendly directions. The RX62T devices allow manufacturers of embedded systems to better address the increased importance that buyers of products such as consumer, industrial and HVAC equipment give to energy efficiency. Primary applications span a wide range: solar inverters, air conditioners, washing machines, lighting controllers and power-factor controllers, among many others.
This announcement closely follows the launch of two other RX600 groups: the RX62N and RX621 MCUs, which feature enhanced connectivity capabilities. All of these devices feature the RX CPU that powers next-generation 32-bit MCUs and integrates the functions of Renesas Technology’s existing 16-bit and 32-bit MCU chips. Besides the fast speed, high performance, and low power consumption that characterize all RX chips, the RX62T MCUs offer the improved motor/inverter control timers and enhanced analog peripheral functions essential for implementing more precise control capabilities and providing value-added features in embedded system designs that are more power efficient.
Controlling three motors simultaneously with one MCU
For example, RX62T MCUs include MTU3 multifunction timer-pulse units, specialized for motor control, which can drive up to two 3-phase motors. The MCUs also integrate a newly developed 16-bit general-purpose PWM timer (GPT) capable of driving a 3-phase motor. With this combination of timers, one RX62T MCU can control up to three 3-phase motors simultaneously. The timers use the same clock as the MCU, which is capable of 100MHz, enabling the timers to produce a wide range of PWM output waveforms with 10 ns resolution.
The floating-point unit (FPU) and improved analog functions built into RX62T MCUs make these devices ideal for use with three-shunt or single-shunt vector-type motor control methods, while also making the chips easier to use. The single-precision FPU offloads the RX CPU and simplifies decimal-point calculations, boosting overall processing performance and simplifying firmware development. There are two 12-bit A/D converter units and one 10-bit A/D converter unit that can capture analog input values from up to 20 channels at a minimum conversion time of 1 us. Each of the A/D units can be triggered by timer units and can sample three phases in parallel.
The 12-bit A/D includes three programmable gain amplifiers and three window comparators. This eliminates external operational amplifiers and comparators used for overcurrent and overvoltage protection. Elimination of these external components reduces system cost and simplifies PCB layout.
Achieving high performance without being limited by flash technology
The MCUs in the RX62T group provide scalable memory solutions from 64KB flash to 256KB flash, and with up to 16KB RAM embedded. An additional independent 8KB of data-flash memory with a background operation (BGO) function is included, allowing data to be written at the same time a program is executing.
The embedded flash memory is based on the renowned Renesas MONOS (Metal Oxide Nitride Oxide Silicon) technology that can be accessed at 100MHz without wait-state insertion. This fast memory, combined with the RX’s Harvard-type architecture, enables the MCUs to deliver 1.65 DMIPS/MHz at any CPU frequency up to 100MHz, without any limitation from flash technology. Despite this excellent level of processing performance, all devices in the RX62T group achieve very low power consumption: only 0.5mA/MHz in full active mode with all peripherals operating. Packages for the new MCUs include 64-pin, 80-pin, 100-pin and 112-pin LQFPs.
To help customers shorten the development cycles of new embedded systems, RX62T MCUs provide a JTAG debugger interface that allows connections to the Renesas E1 and E20 on-chip debuggers and also enables access to similar JTAG third-party debugging products. Moreover, Renesas, third-party suppliers and a global network of alliance partners support RX MCUs with a large, diverse range of hardware and software development tools.
