Research sparks the imagination, but new products pay the bills. In some cases, semiconductor research requires years to reach the production line, with many current new-product developments reflecting research of several years ago. For example, while researchers from Texas Instruments will reveal the results of work on a 0.1-µm complementary-metal-oxide-semiconductor (CMOS) process, engineers at AMI Semiconductor (Pocatello, ID) have employed a 0.35-µm CMOS process to create an RF transceiver chip aimed at the low-power (Zigbee) 802.15.4 specifications. The device integrates an RF transmitter (Tx) and receiver (Rx), as well as a baseband processor. The company's Astric transceiver operates below 1 GHz at 40 kb/s at distances to 100 m using direct-sequence spread spectrum (DSSS) over the 868-to-928-MHz band for applications in medical diagnostic equipment, keyless entry systems, and agricultural equipment.
Similarly, Powerfore, a subsidiary of Tavanza, Inc. (Sunnyvale, CA; powerfore.com), recently introduced the WL2425 wireless-local-area-network (WLAN) power amplifier (PA), fabricated in 0.25-µm RF CMOS. The integrated circuit (IC) consists of three amplifier stages, an input-matching circuit, and power-management circuitry. It delivers +20-dBm linear output power (and 28-dB power gain) at 2.4 GHz with adjacent-channel power ratio (ACPR) of −32 dBc for the first sidelobe and −55 dBc for the second sidelobe. The amplifier operates on a single voltage supply of +2.7 to +3.3 VDC.
Marvell Technology (Sunnyvale, CA; www.marvell.com) has also turned entirely to CMOS for its two WLAN chip sets, one for access points (APs) and one for clients, using the 88W8000 RF transceiver and the 88W8300 baseband/media-access controller (MAC) for clients and the 88W8000 with the 88W8500 10/100 Ethernet/MAC controller for APs. The transceiver has an on-board PA that delivers output-power levels of 0 to +20 dBm in 1-dB steps. The Rx has sensitivity of −88 dBm without using external components. Both processors include clear-channel-assessment (CCA) capability to detect interference and determine how to combat it. The chip sets also include AES encryption capabilities.