Protecting MEMS Pressure Sensors with Parylene

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Protecting MEMS Pressure Sensors with Parylene

Microelectromechanical systems (MEMS) pressure sensors provide accurate measurements for many applications. However, the top side of the piezoresistive MEMS pressure sensor die that has the sensing elements and potentially other circuitry cannot survive exposure to many common items that need to have their pressure measured — including water. To isolate the top surface of the pressure sensor die and other exposed circuitry, parylene is often used as a protective coating. Applied by a vapor deposition polymerization process, the parylene allows pressure to be transmitted to the top side of the pressure sensor to make measurements without damaging or impacting the reliability of the circuitry. The conformal, thin-film coating provides a moisture, chemical and dielectric barrier to protect the sensor’s critical circuitry in medical, automotive and other applications.

In fact, parylene extends the applications that a specific sensor design can address and is part of the packaging expertise that a sensor company may provide. Parylene coating can be found on a wide variety of All Sensors’ products. Specifically, parylene coating is available in all miniature digital product families such as the miniature digital DLVR, DLHR and DLLR Series as well as the millivolt output MLV series and the miniature digital and analog ELVR series.

All Sensors' E1BD Package

 

A protective parylene coating is an option for moisture/harsh media protection in the DLVR, DLHR and DLLR Series E1BD package.

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Do you have a pressure sensing question? Let us know and we’ll address it in an upcoming blog.
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Pressure Sensors and the IoT

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Pressure Sensors and the IoT

The recently published “The Internet of Things (IoT) Sensors Market” report states, “In an Internet of Things ecosystem, two things are very important, the Internet and physical devices like sensors and actuators.” Based on the importance of the sensors, the report projects that the IoT sensors market will reach US$ 23.82 Billion by 2024, at a CAGR of 34.1% between 2018 and 2024.

The analysis includes pressure, temperature, humidity, magnetometer, gyroscope, accelerometer, image and inertial sensors. Segmented into wired and wireless pieces, the IoT sensor market report analyzes Consumer, Commercial, and Industrial market segments.

All Sensors' MEMS Pressure Sensors

Microelectromechanical systems (MEMS) pressure sensors deliver the size, performance, power consumption and cost to satisfy many if not most of the IoT pressure sensing requirements. Based on the variety of measurements that they address, it should not surprise anyone that their data will be used in numerous monitoring and control applications – cloud based or otherwise.

Comments/Questions?
Do you have a pressure sensing question? Let us know and we’ll address it in an upcoming blog.
Email us at info@allsensors.com

Oxygen Tank Pressure

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Oxygen Tank Pressure

For many reasons, patients that require additional oxygen use storage tanks with compressed oxygen to supplement their normal air intake.  The size and subsequent capacity of the tank may vary but the full pressure is typically about 2,000 psi and can go as high as 3,000 psi. With this pressure level in the tank, a regulator converts the supplied pressure to a lower, and much safer, level for the user. With newer aluminum and other materials instead of steel to avoid magnetism problems in situations such Magnetic resonance Imaging (MRI) tests, the pressure level is lower. Minimum pressure in tanks is around 300 psi with delivery systems operating at pressure below 400 psi. In contrast, the storage and delivery system of liquid oxygen in a hospital, pressures are usually around 50.0–55.1 psi. The amount of oxygen present inside the cylinder is measured by the pressure at the outlet nozzle.

PV/T = constant

where P is pressure in the cylinder,

V is the volume of the cylinder,

and T is the temperature

Applied Home Healthcare Equipment

Image courtesy of Applied Home Healthcare Equipment.

Normal clean air contains 19% to 21% oxygen. In contrast, a supply of 60% oxygen with 40% nitrogen is considered acceptable for most clinical purposes but usually high much higher content is available.

Portable oxygen cylinders often have flow and pressure gauges. They provide easy, on sight measurements for a user. However, remote monitoring can use microelectromechanical systems (MEMS) pressure sensors to provide an electrical signal that can be transmitted to one or more receivers.  With this information displayed remotely, a variety of healthcare givers can access and use the information.

Comments/Questions?
Do you have a pressure sensing question? Let us know and we’ll address it in an upcoming blog.
Email us at info@allsensors.com

Correct Pressures for Medical Procedures

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Correct Pressures for Medical Procedures

Gas control, medical control systems, air compressors and vacuum pumps are all possible equipment used in a medical or even a veterinary office. In all of these systems, monitoring and controlling the pressure is necessary to achieve the proper, efficient and safe values.

Patton's Medical gas control panel for nitrogenThe Patton’s Medical gas control panel for nitrogen clearly shows the supply (95 psi) and outlet (82 psi) pressures.

While gages are commonly used so medical personnel can easily observe the pressures during a procedure, microelectromechanical systems (MEMS) sensors could easily be installed behind the panel and then communicate the data to a local or remote monitoring station. With digital data, warnings can be implemented and archived data can be used to show that proper levels of critical elements, such as oxygen, were maintained during an operation.

Comments/Questions?
Do you have a pressure sensing question? Let us know and we’ll address it in an upcoming blog.
Email us at info@allsensors.com