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LN510
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1.2.4 Down-converter Mixers (U2001)
The QSC6075T device performs signal down-conversion for Cellular, PCS and GPS tri-band applications. It
contains all the circuitry (with the exception of external filters) needed to support conversion of received RF signals
to baseband signals. The three down-converting Mixers (Cellular, PCS and GPS), and an LO Buffer Amplifier to
buffer the RF VCO to the RF Transmit Up-converter. The GPS LNA & mixers offer the most advanced and
integrated CDMA Rx solution designed to meet cascaded Noise Figure (NF) and Third-order Intercept Point (IIP3)
requirements of IS-98C and J-STD-018 specifications for Sensitivity, Two-Tone Inter-modulation, and Single-tone
Desense.
Operation modes and band selection are specially controlled from the Qualcomm Single Chip QSC6075T.
1.2.5 Rx RF SAW FILTERs(F1401, F1402)
The main function of Rx RF SAW filter is to attenuate mobile phone spurious frequency, attenuate direct RF
frequency pick up, attenuate noise at the image frequency originating in or amplified by the LNA and suppress
second harmonic originating in the LNA. The Rx RF SAW filter usually called image filter.
1.2.6 RF Receiver(U2001)
The circuit functions of the RF Receive (in QSC6075T) include Rx Automatic Gain Controller (AGC) with 90 dB
dynamic range, quadrature RF mixers, down-conversion mixer from RF to base-band, low pass filters and Analog to
Digital Converters (ADC) for converting to digital base-band. The RFR includes clock generators that drive the
digital processor and a VCO which generates the LO frequency for base-band down-conversion.
Switching system is located in front of the RFR RX_IN_C_LB and RX_IN_C_HB terminal and is for band selection
between cellular and PCS. The Rx AGC either amplifies or attenuates the received CDMA RF signal to provide a
constant-amplitude signal to the I/Q down-converter. The RF output of the Rx AGC amplifier separate into I-channel
and Q-channel base-band components and down-converted by mixer with quadrature LO. LO signals are generated
by a Voltage Controlled Oscillator (VCO) and frequency stabilized by external varactor-tuned resonant tank circuit.
The I/Q down converter outputs the CDMA signals at baseband frequency. Low-pass filtering enables the receiver to
select the desired baseband signals from the effects of unwanted noise or adjacent-channel interference. I/Q base
band components are converted to digital signals by two identical 4-bit ADCs.
LG511C
Содержание LG511C
Страница 1: ...Internal Use Only Service Manual LG511C Date September 2011 Issue 1 0 ...
Страница 28: ...LG Electronics Inc LN510 27 168 Figure 1 1 Block Diagram of LG511C LG511C ...
Страница 30: ...LG Electronics Inc LN510 29 168 LG511C ...
Страница 50: ...LG Electronics Inc LN510 49 168 Waveform Waveform 4 1 1 c 4 1 1 d U1001 pin2 U1003 pin1 ...
Страница 59: ...LG Electronics Inc LN510 58 168 Fig 4 1 2 c Fig 4 1 2 d U1001 pin2 U1003 pin2 Waveform Waveform ...
Страница 96: ...LG Electronics Inc LN510 95 168 1 ...
Страница 98: ...LG Electronics Inc LN510 97 168 1 2 3 4 5 LG511C ...
Страница 108: ...LG Electronics Inc LN510 107 168 Test points Test points 1 TP1 4 TP4 2 TP2 3 TP3 5 TP5 LG511C ...
Страница 118: ...LG Electronics Inc LN510 117 168 Test point Test point TP 2 TP 2 TP 3 TP 4 TP 5 TP 6 TP 7 X 1601 U 1601 F 1601 TP 1 ...
Страница 134: ...LG Electronics Inc LN510 133 168 Appendix Appendix ...
Страница 136: ...LG Electronics Inc LN510 135 168 Appendix 2 Circuit diagram Appendix 2 Circuit diagram ...
Страница 144: ...LG Electronics Inc LN510 143 168 Appendix 3 BGA Pin Map Appendix 3 BGA Pin Map ...
Страница 145: ...LG Electronics Inc LN510 144 168 Not Used 3 1 U1601 BCM2070_BT 3 1 U1601 BCM2070_BT ...
Страница 146: ...LG Electronics Inc LN510 145 168 3 2 U2001 QSC6075T 3 2 U2001 QSC6075T ...
Страница 147: ...LG Electronics Inc LN510 146 168 3 3 U3001 H8BCS0SI0BAR 46M_MEMORY 3 3 U3001 H8BCS0SI0BAR 46M_MEMORY ...
Страница 148: ...LG Electronics Inc LN510 147 168 All Pin Used 3 4 U4004 TSC2007IYZGR_TOUCH IC 3 4 U4004 TSC2007IYZGR_TOUCH IC ...
Страница 149: ...LG Electronics Inc LN510 148 168 3 5 U4002 LM49151_AUDIO AMP 3 5 U4002 LM49151_AUDIO AMP ...
Страница 150: ...LG Electronics Inc LN510 149 168 Not Used 3 6 U5001 BU1851GUW _ Qwerty IC 3 6 U5001 BU1851GUW _ Qwerty IC ...
Страница 151: ...LG Electronics Inc LN510 150 168 Appendix 4 Component Layout Appendix 4 Component Layout ...
Страница 152: ...LG Electronics Inc LN510 151 168 4 1 Main PCB Component Layout 4 1 Main PCB Component Layout ...
Страница 154: ...LG Electronics Inc LN510 1 168 4 2 KEY PCB Component Layout 4 2 KEY PCB Component Layout 4 Hmsdqm k Trd Nmkx ...
Страница 155: ...LG Electronics Inc LN510 1 168 4 2 KEY PCB Component Layout 4 2 KEY PCB Component Layout 4 Hmsdqm k Trd Nmkx ...
Страница 157: ...LG Electronics Inc LN510 15 168 4 3 F PCB Component Layout 4 3 F PCB Component Layout 4 CON104 Hmsdqm k Trd Nmkx ...
Страница 161: ...LG Electronics Inc LN510 1 Appendix 6 Part List Appendix 6 Part List LG511C ...