Skip to Main Content
A heterojunction bipolar transistor (HBT) technology utilizing InGaP/GaAs and carbon-doped base has been established in Motorola's high-volume 6" GaAs facility. The technology has been used to develop an integrated dual band (824-849 MHz and 1850-1910 MHz) power amplifier IC with multi-mode operation for 2.5G portable wireless. Both three-stage amplifiers have 30 dB gain, and provide an EDGE (8-PSK) signal at 28 dBm, an NADC signal at 30 dBm, and a GMSK signal at 32 dBm in their respective frequency bands, using a single 3.5 V source. All matching elements external to the chip are included in a low cost epoxy substrate which is 9/spl times/12/spl times/1.6 mm/sup 3/. Prospects of using this technology in W-CDMA applications have also been explored. A prototype achieves an ACPR of -41 dBc at 28 dBm output power with an efficiency of 36%.