Power efficiency added to low power embedded controller

2nd July 2020
Lanna Cooper

Renesas has expanded its RE Family lineup of embedded controllers with a new ultra-low power consumption member based on Renesas’ Silicon-On-Thin-Buried-Oxide (SOTB) process technology and built around the Arm Cortex-M0+ core. The newest member of the RE01 Group lineup is a 256KB flash memory variant in addition to the 1.5MB flash memory embedded controller, already in mass production.

Featuring a minimum 3.16x2.88mm WLBGA package size, the new embedded controller is optimised for use in more compact product designs in IoT devices for sensor control, for applications such as smart homes, smart buildings, environmental sensing, structure monitoring, trackers, and wearable devices.

The new embedded controller received a certified EEMBC ULPMark-CoreProfile (CP) score of 705, verifying its energy efficiency. This high score was achieved through the use of Renesas’ proprietary SOTB process technology, which enables extreme reduction in both active and standby current consumption.

“We are very pleased that the RE Family embedded controller’s ultra-low power consumption was officially certified,” said Hiroto Nitta, Senior Vice President, Head of SoC Business, IoT and Infrastructure Business Unit at Renesas. “We hope that this will lead to a wider adoption of the RE family, expanding the battery life of embedded devices and relieving more customers of their battery maintenance burden.”

The new embedded controller features current consumption as low as 25μA/MHz during operation and 400nA during standby, placing it among the ultra-low current consumption. Customers can further reduce operation current consumption to 12μA/MHz by using Renesas’ ultra-low Iq ISL9123 as an external step-down regulator.

With ultra-low power consumption, RE Family embedded controllers can dramatically extend the battery life of embedded devices. They are also capable of high speed operation in applications that require real time data processing from multiple sensors, even when powered by compact batteries with very small current output or by energy harvesting devices.

Currently available RE Family MCUs with 1.5MB of flash memory are optimal for applications requiring a large memory capacity, such as image data processing or wireless firmware updating via wireless communication, while the new RE01 Group is optimal for compact devices and IoT devices for sensor control.

Key features of the new RE01 Group R7F0E01182xxx:

  • Arm Cortex-M0+ core with maximum operating frequency of 64MHz
  • 256KB flash memory and 128KB SRAM
  • Operating current: 25µA/MHz (when using on-chip LDO), 12µA/MHz (when using external DC/DC converter)
  • Software standby: 400nA
  • Operating voltage range: 1.62-3.6V with high speed operation of up to 64MHz from 1.62V
  • Package lineup: approx. 3mm square 72-pin WLBGA, 7mm square 56-pin QFN, 14mm square 100-pin and 10mm square 64-pin LQFP
  • On-chip energy harvesting control circuit (fast boot condenser charging, secondary battery charge protection functionality)
  • Approximately 4µA ultra-low power consumption and 14-bit A/D converter
  • Support for flash programming on approximately 0.6mA of power
  • Robust security functions using Trusted Secure IP core
  • Deep standby with Real Time Clock (RTC) operating 380nA at 1.8V

RE Family Development Environment

The EK-RE01 256KB Evaluation Kit can be used in combination with user systems to evaluate all peripheral functions, including energy harvesting systems. The evaluation board included in this kit includes the ISL9123 ultra-low Iq DC/DC converter, which enables measurement of the extremely low operating current of 12μA/MHz.

In addition to the energy harvesting element interface required by energy harvesting systems and a secondary battery connection interface, the evaluation board is equipped with an Arduino-compatible interface to simplify extended evaluation capabilities for sensor boards, and a Pmod connector for extended evaluation using wireless functionality.

Compatible development tools include IAR Embedded Workbench for Arm, which supports the IAR C/C++ compiler, and e2 studio, which supports the GNU compiler - both available free of charge. Driver software supporting Arm’s Cortex Microcontroller Software Interface Standard (CMSIS) is available. A low level sample code for use in low-power applications that cannot permit the power loss from the overhead imposed by driver software is also available.

By strengthening its SOTB-based RE Family product lineup, Renesas aims to help enable an environmentally-conscious smart society by supporting the development of low power systems.

Featured products

Upcoming Events

View all events
Latest global electronics news