The RF2948B is a monolithic integrated circuit specifically designed for direct-sequence spread-spectrum systems operating in the 2.4GHz ISM band. The part includes: a direct conversion from IF receiver with variable gain control; quadrature demodulator; I/Q baseband amplifiers; and, on-chip programmable baseband filters. For the transmit side, a QPSK modulator and upconverter are provided. The design reuses the IF SAW filter for transmit and receive reducing the number of SAW filters required. Two-cell or regulated three-cell (3.6V maximum) battery applications are supported by the part. The part is also designed to be part of a 2.4GHz chipset consisting of the RF2494 LNA/Mixer, one of the many RFMD high-efficiency GaAs HBT PA's and the RF3000 Baseband Processor.