Murata Launches Ultra-Low Power AMR Sensors to Extend Wearable Battery Life
Murata has started mass production of MRMS166R and MRMS168R AMR sensors, targeting ultra-low current draw for battery-powered healthcare, wearables, and IoT devices.
Kyoto, Japan — Murata Manufacturing has begun mass production of two ultra-low power anisotropic magnetoresistance (AMR) sensors aimed at healthcare, wearables, and battery-powered IoT devices.
The company says its new MRMS166R and MRMS168R magnetic sensors are designed for switching applications, where systems need to sense a magnetic field and trigger logic changes—often between active and sleep modes—without relying on mechanical parts.. For consumers, that translates into a familiar promise: longer intervals between battery changes in devices that are meant to stay on or stay ready most of the time, especially when power is limited.
Why ultra-low power AMR sensors matter for battery devices
Many battery-run products rely on automatic mode switching to cut standby consumption.. Whether it’s a gadget entering a low-power state or a system waking on demand, the sensing element has to be both reliable and frugal.. Murata’s core pitch is that the MRMS166R and MRMS168R are built for that job under constrained conditions, including low-voltage operation.
A key challenge in these designs is that coin cell batteries—commonly silver oxide cells at around 1.55 V—offer limited capacity and a narrow operating voltage window.. When the supply voltage drops, sensors that draw more current than necessary can force manufacturers to waste energy elsewhere, or risk unstable performance.. Murata addresses this by redesigning the internal circuitry to reduce current while maintaining dependable operation as voltage falls.
MRMS166R and MRMS168R: different power profiles, same goal
Murata positions the MRMS166R as especially tailored for very low standby drain.. It is described as the first AMR sensor to pair an average current consumption of 20 nA with operation from a 1.2 V supply.. That combination is particularly relevant in compact, coin-cell-powered systems where designers try to stretch usable runtime.
The MRMS166R is also intended for switching in sealed, miniaturized designs.. In practical terms, solid-state magnetic sensing can replace mechanical contact switches, reducing wear and helping maintain reliability when devices are exposed to motion, dust, or everyday handling.. The sensor’s housing is reported at 1.0 × 1.0 × 0.4 mm, reflecting the kind of tight packaging requirements common in wearables and medical electronics.
Murata also introduces the MRMS168R for designs that need stronger drive capability.. The MRMS168R is specified for operation from a 2.0 to 3.6 V supply range, with an average current consumption of 80 nA and a maximum output current noted as higher than the MRMS166R class.. That means the sensor can better support setups where the downstream load demands more current, without changing the broader switching concept.
Healthcare and wearables: contactless switching in everyday hardware
Murata points to healthcare and wearable use cases where magnetic switching can be valuable.. In healthcare, that includes capsule endoscopes and medical patches, where designers often need dependable, sealed functionality and careful power management.. In wearables, it can show up in products like AR glasses and wireless earbuds, as well as security-related IoT devices.
Door open/close detection systems and smart locks are typical examples of security IoT nodes that benefit from contactless magnetic sensing.. These devices don’t just have to work when they’re first installed—they have to keep working with stable performance over long periods, often with batteries that are difficult to replace frequently.
From a user perspective, the improvement is easy to miss until it matters: fewer maintenance cycles, less frequent charging, and fewer moments when an “always-on” feature quietly degrades because the battery is already low.. For manufacturers, better low-voltage current efficiency can also simplify product design choices, because the sensor is one less variable that forces trade-offs.
Looking ahead, Murata says it will continue expanding its AMR sensor lineup and pushing down power consumption further to support longer operating times and more capable functions.. As more devices move toward sealed, miniaturized form factors, the impact of a switching sensor’s standby draw tends to grow—even when the sensor itself remains tiny.
The MRMS166R and MRMS168R are now in mass production, with reported operating ranges that align with coin cell realities and low-power system needs. For more details on the MRMS166R and MRMS168R AMR sensors, Misryoum recommends checking the product pages referenced by the company.