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发表于 2009-5-10 09:41:45
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RF7168
Prelim DS090220
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
Theory of Operation
Product Description
The RF7168 is a dual-band, transmit module (TXM) with fully-integrated power control functionality, harmonic filtering, band
selectivity, and TX/RX switching. The TXM is self-contained, having 50Ω I/O terminals and two symmetrical RX ports allowing
dual-band operation. The power control function eliminates all power control circuitry, including directional couplers, diode
detectors, and power control ASICs, etc. The power control capability provides 50dB of continuous control range and 70dB of
total control range, using a DAC-compatible, analog voltage input. The TX Enable feature provides for PA activation (TX mode) or
RX mode/standby. Internal switching provides a low-loss, low-distortion path from the antenna port to the TX path (or RX port),
while maintaining proper isolation. Integrated filtering provides ETSI-compliant harmonic suppression at the antenna port even
under high mismatch conditions, which is important as modern antennas often present a load that significantly deviates from
nominal impedance.
Overview
The RF7168 simplifies the phone design by eliminating the need for the complicated control loop, harmonic filters, and TX/RX
switch along with their associated matching components. The power control loop can be driven directly from the DAC output in
the baseband circuit. The module has two RX ports for EGSM900 and DCS1800 bands of operation. The 2 RX ports are symmetrical,
they can be used either as EGSM900 or DCS1800. To control the mode of operation, there are three logic control signals:
TX Enable, GpCtrl0, and GpCtrl1. RF7168 offers high efficiency at the rated POUT as backed-off efficiency is improved in
this TXM.
Power On Sequen.. |
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IP卡
狗仔卡
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
显身卡