1998-10-01 , E/DS-1014/12
Product News From Philips Semiconductors

Have you ever wondered why video cassette recorders have ON and STANDBY modes but no ON/OFF power switch like a TV set? If you unplug your video cassette recorder from the wall socket while you're watching a standard TV broadcast channel, you'll find out why. Disconnecting power from the VCR, even when you're not using it, results in a dramatic loss in picture quality.

The reason for this is that the recorder has to remain powered up in order to maintain the vital link between your TV antenna or cable TV set-top box and the antenna input of your TV set. But maintaining this link consumes energy - an estimated 100 kilowatt-hours of electricity every year for a typical recorder. With an estimated 75 million in yearly sales of VCRs, that's a total annual energy consumption of 7.5 billion kilowatt-hours - equivalent to the output of a sizeable nuclear power station.

With the introduction of a unique new transistor, Philips Semiconductors, the largest European semiconductor manufacturer, gives VCR manufacturers the opportunity to save all this energy. The  BF1107 MOSFET (Metal Oxide Semiconductor Field Effect Transistor) conducts the TV antenna signal with no power applied, which makes it the ideal solution for routing this signal through a VCR. For recorders that use the BF1107, TV broadcast pictures will be just as good with the VCR turned off as they are with it turned on.

The BF1107 is not only a better solution, it's also a cheaper solution. VCR manufacturers have previously had to resort to complicated transistor circuits or special GaAs (Gallium Arsenide) transistors to route the TV antenna signal through a VCR - both solutions being considerably more expensive in terms of component and assembly costs. In contrast, the BF1107's ultra-small surface-mount package makes it extremely easy to mount onto printed circuit boards.

The BF1107 is yet another example of Philips Semiconductor's commitment to producing electronic devices that help to conserve valuable energy resources. Like the recently introduced GreenChip™ family of power supply controller ICs and the company's high efficiency switching transistors for fluorescent lighting applications, these innovative solutions make significant contributions to energy saving in consumer appliances.

Philips Semiconductors, a division of Royal Philips Electronics, headquartered in Eindhoven, The Netherlands, is the ninth largest semiconductor supplier in the world and the third largest supplier of discretes in the world. Philips Semiconductors' innovations in digital audio, video, and mobile technology position the company as a leader in the consumer, multimedia and wireless communications markets. Sales offices are located in all major markets around the world and are supported by systems labs.

Technical Note:

Although Philips Semiconductors designed the BF1107 to meet the specific needs of VCR manufacturers, this unique RF switch will find use in a wide range of other applications. For example, its low on-state loss (typically only 1.5 dB) and high off-state isolation (typically 33 dB) make it ideal for RF switching in mobile and cordless telephones, with the added bonus that its zero power consumption will help to increase standby and talk times.