These are Epson's first MCUs to be based on the ARM Cortex-M0+ processor, said to be ARMs most energy efficient. The combination of this and Epson's ultra-low leak process and circuit technology is claimed to help enable powerful MCUs with modest power requirements.
The S1C31W74, which features an operating range of 1.8 to 3.6V and consumes 900nA in RTC mode and 150µA/MHz in RUN mode, is claimed to operate up to two times longer on battery power than an Epson original core 32-bit Flash MCU. Epson says that this level of energy efficiency will move the industry closer to producing smart watches that do not require recharging and IoT terminals for environmental monitoring applications, where power consumption is a critical factor.
The S1C31W74 is housed in a 1mm thick VFBGA8HX-181 package. It includes an LCD driver that can directly display up to 2304 dots, a USB 2.0 full-speed device controller, 512Kbytes of Flash memory, and 128Kbytes of RAM. Epson also plans to offer the S1C31W74 as a bare chip.
Epson will also provide an optional evaluation kit including an evaluation board, debug probe and IDE. The IDE is based on IAR Embedded Workbench for ARM provided by IAR Systems.
