Tire Pressure Sensor Helps Meet Global TPMS Mandates

All vehicles must be equipped with tire pressure monitoring systems (TPMS), according to legislation enacted in the U.S., Europe, and China. By gauging a tire’s pressure levels, a TPMS can alert the driver when under-inflation may lead to unsafe or inefficient driving conditions. In this way, TPMS can prevent tire bursts and the dangers and costs that come with it.

TPMS tire sensors not only cut down on the number of under-inflated tires on the road, but have also been shown to increase fuel economy by 2%, as appropriate tire inflation increases a car’s fuel efficiency. Moreover, maintaining proper tire inflation serves to increase the lifespan of the tire, which is particularly important for commercial vehicles.

The New XENSIV TPMS Sensor

As part of its XENSIVPressure Sensors portfolio, Infineon’s new SP49 TPMS sensor IC features a microcontroller, sensors, wireless communication, and peripherals. It only needs a few passive components and a battery to complete a full automotive TPMS sensor assembly.

The SP49 tire pressure sensor performs all of the functions necessary to implement a complete module for a TPMS.

The SP49 TPMS sensor measures wheel pressure, radial acceleration, temperature, and supply voltage. It also comes with a pressure-auto-ranging feature, which provides pressure accuracy between the range of 100 to 1,400 kilopascals (kPa). This amount of measurement adjustability makes the SP49 a good choice for any kind of vehicle, from passenger vehicles to heavy-duty trucks and other commercial applications.

The tire pressure sensors perform all of the functions necessary to implement a complete module for a TPMS. It’s capable of intelligent tire functions such as on-tire auto-position sensing, tire inflation assistance, tire blowout detection, and load detection.

What Differentiates the SP49 Sensor?

Optimized for battery-powered apps, the SP49 features flexible wake-up, power management, and low power-down current. Its range of supply voltage ensures long-lasting battery lifetime (typical TPMS apps last 10 years with a CR2032 battery). Generating a wake-up from the integrated interval timer, the SP49 is well-suited for standalone remote pressure sensing that demands low charge consumption. It features wake-up capability and what’s said to be best-in-class sensitivity for on-demand measurements.

The device measures pressure in the range from 100 to 920 kPa, acceleration, as well as temperature and supply voltage. An integrated LF receiver and RF transmitter allows for wireless communication. For wired data transfer, the hardware master/slave I2C interface can be used. Further wired interfaces such as UART, SPI, or PWM can be realized in software.

The SP49 is a pin-to-pin replacement for Infineon's last-generation SP40 TPMS products. With its hardware master/slave I²C interface and software-simulated interfaces, the SP49 is best for sub-1-GHz and scalable for BLE TPMS. Available at ASIL A, the sensor offers a high level of integration and is optimized to perform all functions required to implement a modern TPMS module.

The XENSIV SP49 tire pressure sensor can be ordered now.