SA1638BE

INTEGRATED CIRCUITS SA1638 Low voltage IF I/Q transceiver Product specification IC17 Data Handbook 1997 Sept 03 Philips Semiconductors Philips Semiconductors Product specification Low voltage IF I/Q transceiver SA1638 DESCRIPTION The SA1638 is a combined Rx and Tx IF I/Q circuit. The receive path contains an IF amplifier, a pair of quadrature down-mixers, and a pair of baseband filters and amplifiers. A second pair of mixers in the transmit path transposes a quadrature baseband input up to the IF frequency. An external VCO signal is divided down internally and buffered to provide quadrature local oscillator signals for the mixers. A further divider chain, reference divider and phase detector are provided to avoid the need for an external IF synthesizer. Rx or Tx path or the entire circuit may be powered down by logic inputs. On-board voltage regulators are provided to allow direct connection to a battery supply. High performance on-board integrated receive filters with bandwidth tunable between 50-850 kHz Switchable alternative bandwidth setting available to allow channel bandwidth flexibility in operation Designed for a widely used I and Q baseband GSM interface Control registers power up in a default state Optional DC offset trim capability to <200mV Only a standard reference input frequency required, choice of 13, 26, 39 or 52MHz FEATURES Fully compatible with SA1620 GSM RF front-end (see Figure 9) APPLICATIONS Direct supply: 3.3V to 7.5V Two...