Absolute Pressure Sensors in Circuit Boards

One absolute pressure sensor

Introduction

We discuss the candid facts about Absolute Pressure Sensors in this article.

We’ll concentrate on the applications that make use of this component.

Also, we will explain how pressure is measured and why the value of Absolute Pressure is significant.

Lastly, we give you an idea of what kinds of these components are available in the market.

After reading this, we hope you will understand this component’s importance in your electronic device and circuit board.

What are Absolute Pressure Sensors?

There are two major places where you can find Absolute Pressure Sensors today.

These are (1) inside an altimeter and (2) inside a barometer.

Normally, you won’t be aware that these things exist around you.

But surprisingly, they do. These parts are just behind the scenes, hidden in the business of daily life.

For example, your smartwatch has an altimeter; any drone you see has one too.

Weather stations often have barometers that monitor absolute pressure to aid with weather forecasting.

You really can’t do without these tiny electrical components. So we are here to tell you more about it!

Absolute Pressure Basics

To understand the basics of Absolute Pressure Sensors, you need to grasp basic knowledge about pressure.

Pressure is simply described as the amount of force exerted on an object.

There are two ways to measure pressure: (1) using gauge pressure and, (2) using absolute pressure.

For gauge pressure, we can say that it is a relative measure because gauge pressure depends on what is called “ambient atmospheric pressure”. There are some instances when gauge pressure measurement is needed. But we’re not delving into this topic here.

What concerns us is absolute pressure measurement. So, what about it?

When you measure using absolute pressure, you use a perfect vacuum as the basis of the measurement. See this illustration below.

There is, however, a third type of pressure measurement called Differential Pressure.

This type of measurement is a comparison between two pressure readings.

For example, air pressure in plane cabins uses this type of pressure measurement.

How Pressure is Measured Using Pressure Technologies

We are going to concern ourselves with applications using absolute pressure because we are talking about Absolute Pressure Sensors in this blog.

But you must be aware that irrespective of measuring absolute or gauge pressure, all sensors use what are called “Pressure Measurement Technologies” or “Pressure Sensing Principles”. The technology then corresponds to the following kinds of pressure measurement tools:

A potentiometer – It is commonly used to control how loud audio is. Also, it can be found in your Xbox joystick, and under bridges to tell the operator how to adjust the height of the bridge.
A piezoelectric type – Allows for smaller variations in changes, so it is preferred for precision tools like microscopes. Its availability in size small makes it a perfect fit for PIN pads, stethoscopes, ultrasound sticks, and watches
A strain gauge type – Primarily, you know this is working when an alert tells you that the device has reached maximum strain or maximum capacity. You’ll likely see these types inside airplanes, trains, and cars.
Resistive and Capacitive
Optical – These types depend on fiber optic technology
MEMS – these are Surface Mount Devices on a circuit board

So in the end, your Absolute Pressure Sensor tool may use some type of sensing technology—this depends ultimately on the device type.

Absolute Pressure Sensors Used in Electronic Devices

How Absolute Pressure Sensors are Used in Electronic Devices

Absolute pressure sensors are tiny, measuring approximately ≤ 4.00mm.

There are several suppliers out there, but one thing is for sure. This item is very much in demand.

Consider the fact that most smartphones and smartwatches have them. Not to mention countless medical devices, cars, and other vehicles.

The Absolute Pressure Sensor is a component surface mounted on a Printed Circuit Board (PCB).

This tiny component can also be an Integrated Circuit. In the market, it is called “Absolute Pressure Sensor IC”.

By itself, it will not be functional. It has to be connected physically to a PCB. The connections necessary are the data, clock, ground, and power supply.

After the physical connection of the sensor to the board, the next step is programming the device to activate the sensor.

Absolute Pressure Sensor Applications

The following are the primary applications for this component:

Vacuum Packaging

A specific brand of instrument that benefits from this type of component are the Endress + Hauser brand of pressure instruments.
They have quite a variety of offerings including those for vacuum food packaging, dairy production, and concentration measurements.
Some of these sensors are made of ceramic to withstand high heat during the pasteurization process
MEMS Pirani-type vacuum transducers and sensors are also available.

Health Applications

The most common examples are sensors for monitoring activity (personal & sports use).
Others are used for the storage of toxic and non-toxic gasses, in laboratories
Particulate matter, humidity sensors, as well as temperature sensors
Hospitals use sensors like oxygen concentrators, hemodialysis machines, anesthesia machines, ventilators, ultrasound machines, and so on.
Sensors can also be worn by patients outside the hospital setting. This is helpful because it facilitates remote monitoring, with minimal disruption to patients’ lives.
Breath analyzers for detecting alcohol is used in medical + law enforcement setting

Automotive Electric Control Unit

To set the ignition time properly in a car, you need information from this component. Additionally, you require it to determine the ideal ratio of fuel to air.
Another place where the component would belong is the MAP sensor. It is needed to calculate engine combustion.
Emission control systems and vehicle safety enhancement systems are two other applications.
The sensors must be able to endure temperatures ranging from -40° to 140° Celsius and even a bit higher.

Machine Calibration

In many types of industries, machines are used for production. All of these machines need to be calibrated to ensure accuracy in performance.

Absolute pressure sensors can be used to calibrate these machines.

Machines need to be calibrated in terms of:

Volume
Gas concentration
Pressure
Acceleration
Speed/velocity
And so much more

Absolute Pressure Sensors in Your Printed Circuit Board

There is a range of diverse product offerings for these components intended to be mounted on PCBs. We describe some of them:

Those intended for digital and analog signals
Dedicated design for harsh environments (waterproof types, high heat resistance types)
Classified according to mbar pr bar (with a range of availability from 0 mbar to 16 bar)
Differentiated according to mmHg
Ranked according to psi (Pound per square inch)
Classified in terms of Surface Mount of Through-Hole Mount
With I2C output, so that other IC chips can communicate with it
Can have switches integrated with sensor

As you can see, there is definitely a sensor that can suit your needs. If you don’t have an idea about how to choose one, you can refer to the end goal of your device and your KPIs.

The types of circuit boards that are suitable for Absolute Pressure Sensors are the following:

Multilayer PCB – These are wireless, digital PCBs that can be used as monitoring devices, and they support Wi-Fi6.
HDI PCB – For this type of high-performance board, either a rigid PCB type or a flexible HDI PCB type is appropriate.
High-Frequency PCB – This operates between a frequency range of 500 MHz and 2 GHz. These boards enable increased signal flow speed.
Radio Frequency PCB – Are you familiar with RFID? Then, you already know why you need sensors for this board.

Some Applicable PCBs

In addition:

Infrared PCB – The boards that belong to this classification use IR sensors. Some of these are suited to measure absolute pressure.
Ultrasonic PCB – A major application of this board is proximity sensing (distance measurement). Its mainly found in hospital/laboratory settings
5G PCB – For faster data transfer, 5G is necessary to transmit the sensor’s information
Waterproof PCB – As we have mentioned earlier, the use of this type of PCB is sometimes necessary when the setting is prone to wetness
Transparent PCB – There can be various applications that necessitate the aesthetics of a transparent PCB.

Conclusion

We discussed the idea of pressure about our topic in this post.

Then, we made it apparent that a variety of technological approaches are employed to determine absolute pressure.

We then discussed the uses of absolute pressure sensors in everyday life.

We were aware of how crucial these elements are to how businesses operate.

Finally, we looked at the sensor’s role in circuit boards.

This brings us to the part of the conversation where we identify ourselves as a PCB provider to you.

Since 2008, PCBMay has been producing PCB bare boards.

Additionally, we provide PCB assembly, either through-hole or SMD, where we will precisely place your sensor on the board.

For any PCB and PCBA inquiries, please contact us through chat, email, or phone call.

Absolute Pressure Sensors: What You Need to Know