In-Depth Understanding of TPMS: Technology, Benefits, and Future Trends

Familiar with cars, people know that TPMS (Tire Pressure Monitoring System), SRS (Supplemental Restraint System), and ABS (Anti-lock Braking System) are the three major safety systems of a car.

TPMS, or Tire Pressure Monitoring System, integrates automotive electronics technology, sensor technology, and wireless communication technology. It is a safety auxiliary system installed on car tires to monitor tire pressure in real-time.

"The engine is the heart of the car, and tire pressure is the blood pressure of the car." Both high and low tire pressure can have an impact on the car's driving.

Since 2020 in China, all new car models are required to be equipped with tire pressure monitoring functions to ensure driving safety. The role of TPMS is to monitor tire pressure automatically and in real time. Once it detects a tire leak or low pressure, it will issue an alarm to remind the car owner to check and repair in time, preventing accidents caused by tire problems. In addition, tire pressure monitoring also helps to reduce fuel consumption, reduce tire wear, and improve driving efficiency and economy. Indirect tire pressure monitoring monitors tire pressure by comparing tire rolling radius, while direct tire pressure monitoring uses internal pressure sensors to monitor in real time.

Some people who use the tire pressure monitoring system for the first time may ask - why doesn't the tire pressure monitoring system display anything after it's turned on, and only shows after driving for a few minutes?

There are two reasons for this:

• To save power, if the RF communication is maintained during the parking period, the power consumption of the tire pressure sensor will be very fast. Despite the low-power design, it is still necessary to save electricity. So during the parking period, it will enter a quasi-sleep state. Only when the vehicle starts to operate, it will maintain continuous signal transmission. The HS1912 micro vibration sensor produced by Hondsun Company plays an important role in the power management of tire pressure monitoring products.

• After the tire starts to move, the pressure is more uniform, and the temperature also rises to a certain extent, so the tire pressure information is more accurate than when it is static.

Now, the commonly used tire pressure detection sensor circuits on the market rely on small-capacity batteries for power supply, but the battery power limits the service life of the sensor, the detection frequency during operation, and the complexity of sensor design, production, manufacturing, and system application debugging also increases accordingly. At the same time, it also brings environmental protection issues after battery waste.

The good news is that there are now passive (battery-free) technology solutions, which are applied to direct automotive tire pressure monitoring systems, providing power and stable electrical signals for tire pressure detection sensors. Compared with traditional solutions, this solution significantly reduces the quality of the sensor, reduces the impact of the battery on the system, and improves the overall performance and environmental protection of the system.

With the advancement of technology, passive TPMS is expected to occupy a larger share of the future automotive market. Its long-term stability and reduced maintenance costs will make it a standard configuration for more vehicles. This means the market for us, Hondsun sensor manufacturers, is become smaller, but I think technological progress is a major manifestation of human progress, and we are still happy about it.

Hondsun，a professional R&D and production of electronic components and sensors.