ASIC Driver Safety Systems

As the world leaders in automotive ASIC applications SWINDON takes safety very seriously

With the ever increasing awareness of personal safety and protection within vehicles, SWINDON provides a market leading solutions for a growing number of applications but in particular Tyre Pressure Monitoring Systems (TPMS) that provided the driver with unprecedented levels of safety and reliability.

Constant product development and state of the art innovation has meant that the SWINDON solution provides the market with many years of reliable, safety driven products and solutions.
Our years of experience in designing and supplying innovative ASIC solutions has resulted in SWINDON Silicon Systems being the preferred partner of choice for many marques of Car, Commercial Vehicles and Trucks.

Take a closer look at the SWINDON TPMS ASICs

The SWINDON world leading TPMS ASICs are a family of battery powered products designed to meet the demands of low cost and operation in the harsh environment of a wheel on a vehicle. The designs comprise a custom micro-controller with embedded software which control several peripheral functions used in the process of measuring pressure, temperature and RF transmission.

Each ASIC has a highly sensitive, polled motion detector circuit which provides a wake-up feature to the micro-controller. The embedded software dictates the sequence of events thereafter which can vary depending on customer requirements. Typically a pressure and temperature measurement would occur, any change from the previous value would activate the PLL based RF transmitter and deliver encoded data for reception by an RF receiver.

Accurate TPMS System Components using SWINDON ASICs

A MEM’s pressure sensor is calibrated to each ASIC with the calibration data being stored in OTP memory. The output signal is fed to an instrumentation amplifier for signal conditioning before A to D conversion. The A to D converter uses sigma delta modulation followed by a digital filter, the result is then corrected for offset and temperature before being stored in RAM.

A small single cell lithium battery is used to power these ASICs where an operating life of 10 years is a requirement. The management of power consumption has been an important aspect of the design philosophy. The circuit features a very low power trimmed internal oscillator to control all the essential timing and operates continuously. Numerous safety mechanisms are included to prevent any lock-up of the device.

A low frequency 125KHz ASK receiver is provided as an external interface for module control and diagnostic purposes once the ASIC module is placed inside the wheel.

Look at these SWINDON developed features…

• Power management to ensure a 10 year battery life
• Very low power calibrated internal oscillator +/0.5%
• Ultra low sleep current of typically 500na
• Highly sensitive motion detection interface < 0.5mV
• Integrated FM/ASK RF transmitter for ISM band 315/433 MHz
• 125KHz LF ASK receiver with input sensitivity < 0.5mV
• 12 bit sigma delta ADC for measuring pressure and temperature
• Incorporates high performance patented wheel position technology
• OTP and EEPROM available