ST Micro's start/stop chips will lead to greener cars

ST Microelectronics is working on a new range of chips that allow in-car entertainment equipment to operate without interruption as the engine is turned off and restarted.

The first of these is the TDA7850LV, which is a 4x50W audio power amplifier. According to  ST this is the first start/stop-compatible IC of its kind in production and includes features such as Hi-fi class distortion and low output noise, yielding high sound quality and an integrated 0.35A high-side driver supporting functions such as antenna control.

It also provides protection against common vehicle electrical hazards such as short circuits to ground and battery and engine over heating.

ST’s new audio chip is just the start – according to the company some manufacturers estimate that start/stop technology could be a huge contributor to reducing energy usage and cutting fuel consumption by around 20 percent.  

In the future we could see some systems shutting down the engine when the car is stationary at traffic lights, drive throughs and zebra crossings and automatically restarting when the driver prepares to move on.

And, according to market analyst Strategy Analytics, annual demand for vehicles featuring start/stop is expected to reach almost 20 million units by 2015, which will initially be led by customer demand in Europe.

This technology is said to be energy efficient as the start/stop supply voltage for on-board electrical equipment could fall to as low as 6V when the engine is turned off and restarted. This is because only the battery is supplying electrical power.

ST says it is building a complete family of start/stop audio power amplifiers that will include entry-level class-AB amplifiers, digital devices with diagnostic features, and a lass-D family offering “outstanding” power efficiency.

In addition to its start/stop compatibility and high audio performance, the TDA7850LV offers different configurations including vertically or horizontally mounted packages. There’s also a new surface-mount variant, which allows car-audio makers to take advantage of high-speed fully automated assembly enabling increased throughput and production quality.

The TDA7850LV is currently ramping-up mass production.