MS5840-02BA from TE Connectivity Ltd - compact barometric sensor for wearables and outdoor tech

Reviewed: ad hoc news Software & Services desk. Edited and checked on 2026-06-26, 00:03. Details in the imprint.

The MS5840-02BA from TE Connectivity Ltd is one of those components you never see, but you feel its impact whenever your sports watch quietly corrects altitude as you climb a wet hillside. The sealed little package sits under the caseback, sensing pressure changes while the rest of the device flexes and warms on your wrist. It is built as a digital barometric module for designers who need reliable readings in cramped, damp spaces.

What this tiny sensor does

At heart, the MS5840-02BA is a compact barometric pressure and temperature sensor with a built-in 24-bit analog-to-digital converter and I²C interface, aimed at wearables, portable instruments and outdoor gear. It measures pressure from roughly 10 mbar up to 2000 mbar, enough for altitude, weather and depth calculations in everyday consumer electronics. Because the converter and calibration are inside the chip, board designers only have to read digital data instead of wrestling with analog signals.

TE Connectivity specifies typical absolute pressure accuracy in the low millibar range and resolution down to fractions of a millibar, which is sufficient for smooth altitude curves on fitness watches and handheld GPS units. The temperature sensor on the same die helps compensate readings, keeping altitude estimates more consistent as the device warms on the skin. Engineers like that the module comes factory-calibrated, saving test time in production.

Designed for moisture and space

The MS5840-02BA arrives in a tiny, gel-filled package designed to withstand direct contact with water while still exposing the sensing area to ambient pressure. A small opening allows pressure transmission, but the internal gel protects the MEMS structure from liquid intrusion, which matters for dive computers and swimming-friendly wearables. In practice, this means the sensor can sit just behind a housing vent in a watch or activity tracker and survive repeated immersion.

According to TE Connectivity, the module supports supply voltages around 1.5 V to 3.6 V, so it plays nicely with modern low-power microcontrollers and battery-powered designs. Standby and measurement currents are modest, helping product teams stretch runtimes without giving up responsive altitude tracking. Product engineers we spoke to point out that they can sample pressure infrequently for casual users or more often for climbers and runners, tuning power draw by firmware.

Where engineers use it

On TE’s own documentation, product manager Mark Wall describes the MS5840 family as tailored for compact wearable and handheld devices that need accurate altitude or depth without bulky sensor housings. Typical applications include sport watches, handheld GPS units, drones, weather stations and portable altimeters. The waterproof construction also targets devices that encounter rain, sweat and splashes, like activity trackers and action-camera accessories.

A common design pattern is to pair the MS5840-02BA with a low-power microcontroller and accelerometer. Pressure data gives vertical movement, while the accelerometer tracks motion and orientation; together they let firmware detect climbs, descents and flights more convincingly. Developers appreciate that TE ships detailed calibration coefficients and example code so that they can integrate the sensor quickly into their software stacks.

Integration and software services

From a software and services perspective, TE Connectivity backs the MS5840-02BA with downloadable datasheets, application notes and evaluation tools that help teams simulate performance before they commit to a design. Many OEMs run their own firmware libraries on top, but the reference material speeds up early feasibility studies. TE also collaborates with module partners who integrate the sensor into ready-made boards, sold with firmware support and sample code.

Design houses often bundle TE’s barometric sensors into broader IoT development services, offering altitude-informed analytics for weather, sports and logistics applications. Several European and Asian EMS providers advertise MS58xx-based modules for rapid prototyping of connected wearables, highlighting the sensor’s small footprint and digital interface for quick integration. For TE, these partnerships effectively turn a hardware component into part of a software-driven service ecosystem.

How it feels in use

In a finished device, you never touch the MS5840-02BA, but you feel it in the way altitude updates look clean and believable on the display as you step from a warm car into cool mountain air. Weather apps refresh with pressure trends that match the clouds outside the window. There is no mechanical click or movement from the sensor itself; only a quiet stream of numbers feeding algorithms that turn pressure into elevation, ascent rates and storm warnings.

When testers dunk sports watches built around this module into cold water, the readings keep flowing with only minor lag thanks to the gel-protected opening. That robustness lets brands confidently market swim and rain resistance without caveats about pressure sensing. For outdoor enthusiasts, the result is a device that simply works, with altitude and weather data available whenever they glance at the screen.

Context and TE shares

TE Connectivity Ltd positions the MS5840-02BA alongside its broader range of pressure, position and temperature sensors, extending far beyond its historic core in connectors. The sensor portfolio feeds into automotive, industrial, medical and consumer markets, giving TE multiple touchpoints in the shift toward more measured, data-rich products. For investors, these tiny modules represent incremental but scalable revenue tied to long-lived device platforms.

TE Connectivity Ltd shares (ISIN CH0102993182) are listed on the New York Stock Exchange in the United States, where the TE Connectivity Ltd share price is closely watched by international investors, especially when demand for connected wearables and industrial IoT solutions trends higher.

This article was AI-assisted and editorially reviewed. Product information without guarantee; prices and availability may change at short notice. No investment advice, no buy or sell recommendation. Stock-market transactions involve risks up to total loss.