Renesas configures MCU family around industrial/consumer designs

January 25, 2016 // By Graham Prophet
The RX230 group of microcontrollers extends the RX231 group of 32-bit MCUs, for cost-sensitive applications, combining digital signal processing (DSP) and floating point unit (FPU), and low power consumption.

With 1.8V to 5.5V supply, the RX230 Group is aimed at applications that require high processing performance in environments with low current supply capacity, as well as the robustness needed in home appliance applications.

Compared to the existing RX231 Group, the RX230 is optimised with regard to embedded flash size and feature. This covers the requirements of cost-sensitive industrial and consumer applications that do not require USB nor CAN interfaces, can fit their code in 256 kB flash or less, and need a a maximum of 32 kB embedded RAM.

The RX230 Group can handle high processing loads, such as eliminating noise from digital signals and performing floating-point calculations, by using Renesas’ powerful 32-bit RXv2 CPU core with DSP/FPU operation capabilities. System power consumption is not only reduced by applying the latest Renesas process technologies, but also by reducing the CPU frequency and boosting the processing speed at the same time. The RXv2 CPU core as implemented on the RX230 achieves a performance benchmark score of 4.16 CoreMark/MHz, which Renesas says is leading edge in its class. RX230 achieves power performances in standby of 0.8 μA, which enables system manufacturers to extend system operation on battery power.

Operating speeds is up to 54 MHz, with an approximately fourfold increase in DSP performance and sixfold in FPU performance. As a result, the new MCUs significantly reduce the time required for high-processing load tasks such as digital filtering. At 0.8 µA in standby mode the contents of both SRAM and CPU registers are retained. The RX230 Group can recover from standby mode in a minimum of 5 µsec, which makes it possible to reduce current loss during the recovery and allow the application to react quickly to external events. Applications can be executed from flash after this time, and analogue functions, such as the analogue-to-digital converter, are available for use.

The RX230 Group also supports an additional low power timer (LPT), which only consumes an additional 0.4 µA and allows the system manufacturer to program the device to wake up from the low power modes with a very wide range of possible timings, minimising current consumption in many different applications.