At a time when engine start/stop technologies are being employed by car makers to reduce fuel consumption and carbon emissions, ST Microelectronics , a world leader in automotive ICs is pioneering a new generation of chips that allow in-car entertainment equipment to operate without interruption as the engine is turned off and restarted.
The TDA7850LV is a 4x50W audio power amplifier and the very first start/stop-compatible IC of its kind in production.
Some manufacturers estimate that start/stop and other technologies such as high-efficiency engine management programs could be a big contributor to reducing energy usage, cutting fuel consumption by as much as 20% in certain models over the coming years.
The start/stop system shuts down the engine when the vehicle is stopped and restarts as the driver prepares to move off. According to market analyst Strategy Analytics, annual demand for vehicles featuring start/stop is expected to reach almost 20 million units by 2015, initially led by customer demand in Europe.
In cars fitted with start/stop, the supply voltage for on-board electrical equipment can fall to as low as 6V when the engine is turned off and restarted with only the battery supplying electrical power.
In addition, switching between battery power and alternator power can generate 'pop and click' noise. Left unaddressed, these effects can cause noticeable distortion in the audio system's output. Hybrid-electric vehicles present similar challenges to electronic equipment designers.
Discrete components external to the audio power amplifier can be used to build circuitry to regulate the supply voltage and suppress pop and click noises. However, these circuits complicate design and add significantly to bill-of-materials costs.
ST's TDA7850LV audio power amplifiers eliminate the use of these components, simplify design, reduce cost and save PC-board space.
ST is building a complete family of start/stop audio power amplifiers that will include entry-level class-AB amplifiers, complex digital devices with diagnostic features and an automotive class-D family offering outstanding power efficiency.
Fabio Marchio, Automotive Product Group Vice-President and General Manager of ST's Automotive Infotainment Division says that ST's emerging family of devices, beginning with the TDA7850LV combines advanced start/stop capability with the hi-fi audio quality and outstanding ruggedness that have always distinguished ST's audio power ICs and ensured their strong market leadership.
Key benefits of TDA7850LV audio power amplifiers
- Start/stop compatibility and high audio performance
- Delivers the advantages of ST's Flexiwatt power package - the standard for car audio ICs
- Several configurations available including vertically or horizontally mounted packages
- Unique new surface-mount model
- 4x50W MOSFET output stage
- 2Ω output driver compatible with diverse speaker types
- Hi-fi class distortion and low output noise, yielding high sound quality
- Integrated 0.35A high-side driver supporting functions such as antenna control
- Protection against common vehicle electrical hazards:
- Short circuits to ground and battery
- Open-circuited speakers
- Highly inductive loads