The STMicroelectronics LPS33W water-resistant MEMS pressure sensor combines chemical compatibility, stability, and accuracy for use in a wide range of applications such as fitness trackers and other wearables, vacuum cleaners, and general-purpose industrial sensing.
Protected by a viscous potting gel inside the cylindrical metal package, the IPx8-rated LPS33W withstands salt water, chlorine, bromine, detergents such as hand soap and shampoo, e-liquids, and light industrial chemicals such as n-pentane. The package lid provides high corrosion resistance, and the cylindrical form factor is easy to use with o-rings in applications that require a sealed enclosure.
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| LPS33W internal structure. |
The unique properties of ST’s proprietary gel formula, together with the sensor’s built-in signal-conditioning ASIC, ensure class-leading 0.008 hPa RMS pressure noise thereby allowing outstanding measurement resolution. Susceptibility to reflow-soldering stress during assembly is also extremely low, drifting less than ±2 hPa and recovering normal accuracy in 72 hours; more than twice the speed of other sensors. Temperature compensation keeps accuracy within ±3 hPa over the operating range from 0 °C to 65 °C.
The LPS33W operates at just 15 µA in high-performance mode, with a 3 µA low-power mode and 1 µA power-down to help maximize runtime of battery-powered devices. A generous 1280-bit FIFO stores up to 32 slots of 40-bit pressure and temperature data, helping save extra power by minimizing intervention from the host microcontroller. A low-pass filter and I2C and SPI digital interfaces are also built-in.
The LPS33W is in mass production now, in a 3.3 mm-diameter × 2.9 mm cylindrical metal case, priced from $3.60 for orders of 1000 pieces.
