1997-06-27 , E/DS-485/120

Philips Semiconductors has introduced a family of silicon bipolar microwave power transistors targeted for use in S-band pulsed radars, including a unique 110-watt transistor with the 400-MHz bandwidth required to cover the entire 2.7 GHz to 3.1 GHz frequency range. Until now, transistors capable of handling such high powers were only capable of covering half the required frequency range (either 2.7 GHz to 2.9 GHz or 2.9 GHz to 3.1 GHz).

The BLS2731 family includes four transistors with minimum pulse-power handling capabilities (tp = 100 µs, d = 10%) between 10 W and 110 W. The 10 W, 20 W and 50 W devices in the family all feature a typical power gain of 8 dB and a typical collector efficiency of 40% over the 2.7 GHz to 3.1 GHz range. Corresponding figures for the family's 110 W device are typically greater than 7 dB gain and greater than 35% efficiency. All four transistors have a V_CB rating of 40 V.

"The availability of high power transistors with the 400-MHz bandwidth required to cover the entire 2.7 GHz to 3.1 GHz band is a major breakthrough that will reduce both the cost and complexity of medium power radars," said Peter Wolf, Product Marketing Manager at Philips Semiconductors' wafer fab in Nijmegen, The Netherlands, where these transistors are produced. "Philips also has the advantage of being one of the few suppliers that can produce S-band transistors in high volume," he added.

All the transistors are housed in 2-lead rectangular flange packages. Internal input and output matching networks simplify the design-in process. Integral emitter ballasting resistors and gold metallizations ensure exceptional ruggedness under adverse operating conditions and excellent long-term reliability.

In addition to their targeted application in civilian and military air traffic control and defence radars, these high-performance power transistors are also suitable for use in microwave communications equipment.

Low volume prices start at around Hfl 500 per device. Samples are available now, with volume production scheduled to begin in the second quarter of '97.

Philips Semiconductors, a division of Philips Electronics NV, 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.