LG GB160, Руководство по обслуживанию

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To dramatically reduce the BOM both TX Translational loop and main PLL Loop Filters are fully
integrated into the device.
AD6548 incorporates a complete reference crystal calibration system. This allows the external
VCTCXO to be replaced with a low cost crystal. No other external components are required. The
AD6549 uses the traditional VCTCXO reference source.
The AD6548/9 also contains on-chip low dropout voltage regulators (LDOs) to deliver regulated
supply voltages to the functions on chip, with a battery input voltage of between 2.9V and 5.5V.
Comprehensive power down options are included to minimize power consumption in normal use.
A standard 3 wire serial interface is used to program the IC. The interface features low-voltage
digital interface buffers compatible with logic levels from 1.6V to 3.0V.
The AD6548/9 is packaged in a 5mm
×
5mm , 32-lead LFCSP package.
3.3.2 Features
Fully Integrated GSM Transceiver including
Direct Conversion Receiver
4 Differential LNAs
Integrated Active RX Channel Select Filters
Programmable Gain Baseband Amplifiers
Translation Loop Direct VCO Modulator
Integrated TX VCO and tank
External TX filters eliminated
Integrated Loop filter components
High performance multi band PLL system
Fast Fractional-N Synthesizer
Integrated Local Oscillator VCO
Fully Integrated Loop filters
Crystal Reference Oscillator & Tuning System (AD6548)
Power Management
Integrated LDOs allow direct battery supply connection
Small footprint
32-Lead 5 X 5 mm Chipscale Package
APPLICATIONS
Dual, Triple and Quad Band Radios
- GSM850, E-GSM 900, DCS1800 and PCS1900
- GPRS to Class 12- EDGE RX
ORDERING GUIDE Model TemperatureRange Package
AD6548BCPZ -20°C to +85°C LFCSP-32
AD6549BCPZ -20°C to +85°C LFCSP-32