LOW POWER DIRECT CONVERSION RF TRANSCEIVER ARCHITECTURE AND ASIC AND SYSTEMS INCLUDING SUCH

摘要

A direct conversion RF transceiver (2) and ASIC having an on-chip voltage controlled oscillator operating frequency that is half of the transmitter (4) and/or receiver (6) operating frequency, the VCO (20) being comprised of a plurality of synchronized LC oscillators (92A-D) introducing precise phase shifts that eliminate frequency ambiguity. The transceiver incorporates several low power circuits, including on-chip a power converter switchably coupling a capacitor (42) to a power supply (45) and to an electrical load (40), multiple switchable low dropout regulators (60A, B) each coupled to alternate power supplies (62, 64) and having electrical components (67A, B) for setting the bandwidth of the respective low dropout regulator. The transceiver also includes a FSK digital modulator utilizing a circuit-implemented polynomial piecewise approximation (71) of a raised cosine signal.