Smart meter wireless chip has worldwide RF compatibility

October 28, 2016 // By Graham Prophet
Rohm Group company Lapis Semiconductor has announced a sub-GHz wireless communication LSI optimized for applications requiring low power consumption over relatively long distances, such as smart-agriculture, gas/fire alarms, smart meters, and home/building security systems. The new devices feature worldwide compatibility, high reliability and energy efficiency.

This sub-GHz wireless LSI is aimed at smart meters and wireless networks around the world. The ML7345 covers a wide range of sub-GHz frequencies (160 MHz to 960 MHz), providing universal compatibility. Improving high-frequency amplifiers makes it possible to achieve class-leading wireless performance and environmental stability (more than 3x the transmission power temperature resistance), simplifying wireless network configuration (i.e. of smart meters) while improving reliability (e.g. reducing the number of relays). In addition, a high-speed radio wave check function that performs receiver startup in a short period of time, combined with significantly reduced sleep current during standby (which accounts for the majority of communication time), decreases average current by 48% compared with conventional products, leading to lower system power consumption and longer battery life.


Broad compatibility (160MHz to 960MHz) ensures compliance with the ARIB STD-T108 standard in Japan as well as IEEE802.15.4g, enabling global support for applications such as smart meters and energy management systems (EMS).

The ML7345 is compliant with the latest (2013) version of the Wireless M-bus standard. Improvements made over the conventional Wireless M-bus packet handler ensures support for the newest extended packet specifications.

High output (100 mW) is optimized for the Chinese market in a variant coded ML7345C. Along with 100 mW antenna output, the ML7345C delivers programmable receiver bandwidth settings that support a wide range of specifications, from electricity, gas, water, and thermal meters to crime and disaster prevention systems.

In addition to improving high-frequency amplifier performance, a transmission power variation of less than ±1dB is ensured across the entire operating temperature range, providing more than 3x the stability of conventional products. This allows for network design without the need to consider margins in response to environmental changes in complicated wireless networks such as smart meters that require multi-hop operation, contributing to lower costs and simpler network configuration (i.e. no relays). High reliability communication can be achieved in relatively simple wireless networks used for