SKY74693

www.DataSheet4U.com PRODUCT SUMMARY SKY74693: Receiver for CDMA, AMPS, PCS, and GPS Mobile Handset Applications Applications Tri-band, tri-mode handsets PCS and GPS phones CDMA and GPS phones Except for the Surface Acoustic Wave (SAW) filters, a UHF Voltage Controlled Oscillator (VCO), and matching components, the device incorporates everything required to implement the receiver chain, from the Low-Noise Amplifier (LNA) to the In-Phase and Quadrature (I/Q) demodulator stages. Three LNAs are in the frontend receiver: a three-step gain stage cellular LNA (high, mid, and bypass), a two-step gain stage PCS LNA (high, bypass), and a high gain stage GPS LNA. After RF LNA signal amplification and filtering from the antenna, the received signal is mixed down from RF to the IF. There are separate mixers for AMPS, CDMA-cellular, CDMA-PCS, and GPS modes. To use a single IF frequency plan, the CDMA and PCS mixer outputs have been combined. Therefore, both CDMA and PCS bands use the same IF SAW filter. The AMPS differential output can be combined externally to mate to a single-ended SAW filter. The GPS mixer is an image-reject mixer, which eliminates the need for an external RF SAW filter between the LNA and mixer. The GPS image-reject mixer has a differential output for an external L-C bandpass filter. After IF filtering, the IF signal is amplified by a Variable Gain Amplifier (VGA) and fed to an I/Q demodulator, resulting in baseband I/Q signals at the output. The SKY74693 is al...