Sony Semiconductor Launches GPRS & EDGE Transceiver

Sony Semiconductor has launched its first Quadband GSM/GPRS /Edge transceiver, the DuettoDC, which supports the 4 GSM bands 850/900/1800/1900 and is GPRS/Edge compatible. Incorporating a direct conversion receiver and direct modulator on transmit, the DuettoDC is designed for lowest RF BOM (Bill of Materials) and supports GPRS Class 12 and both Edge receive and transmit. The exceptional level of integration means key functions such as the RF VCO, all LNAs and VCTCXO blocks are on chip, whilst the high power output direct modulators eliminate the need for costly external power VCOs or PA predrivers. It is also compatible with most major GSM Basebands through a flexible/programmable RF to Baseband interface.

The DuettoDC includes a fast hopping Sigma Delta PLL enabling GPRS class 12. The low PLL spurious and phase noise result in improved receive blocking performance. Traditional direct conversion problems of static and dynamic DC offsets are minimised through a combination of high IP2 RF mixers and a programmable/automated DC offset correction routine. The latter stores the offsets digitally and corrects them through DACs for low drift. This makes a GPRS handset less sensitive to unwanted blocking signals and enables it to maintain high data rate transfers using multiple timeslots. The DuettoDC is fabricated in a leading edge 0.25um SiGe Bicmos process and is packaged in a space saving 84pin VFLGA (7.0x7.0x1.1mm)."

Posted to the site on 4th February 2002