RF LNAs Help Outfit Cell Phones

With an eye on current and next-generation cellular handsets, a suite of integrated, low-power low-noise amplifiers (LNAs) are offered for designers of tri-band GSM800, DCS1800 and PCS1900 cell phones. The IBM3604011S010 LNA provides a noise figure of 1.3 dB typical in the GSM band, 1.5 dB at DCS1800, and 1.9 dB at PCS1900 while consuming just 6 mA. It also features a high reverse isolation, reducing the need for extra filters by directly converting the RF signal to baseband. In addition, two SiGe-based, single-band LNAs for GSM handsets are available: the IBM43RCLN1115 supports GSM and the IBM43RCLNA1116 is for GSM operation at 1,800 MHz. Both devices have a gain of 25 dB and a reverse isolation of 40 dB typical. IBM MICROELECTRONICS, East Fishkill, NY.