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Texas Instruments TRF1500 manual

Models: TRF1500

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SWRA004A

High-Band Cascaded Receiver Section: LNA, Mixer, LO Buffer Amplifier

Cascaded High-Band Receiver Section: LNA, Mixer, and LO Amplifier

The TRF1500 high-band receiver section, shown in Figure 11, is an integrated front-end down converter designed to operate in the 1900 MHz frequency range. The high-band down converter consists of an LNA, an image-reject mixer, and LO buffer amplifier circuitry. Figure 11 details the cascaded block diagram with the image reject mixer detailed inside the dotted box.

The digital control allows the high-band receiver to operate in three different states to compensate for the environment in which the TRF1500 is operating. The high-band receiver can be operated in the normal state, where the LNA, mixer and buffer amplifier are on, the strong signal state, where the LNA is off and the mixer and buffer amplifier are on, or the transmit state, where the LNA bias current is increased to prevent compression when the transmitter is on.

The high-band receiver has a typical nominal gain of 26 dB, an IIP3 of -17.7 dBm and a noise figure of 4.66 dB when the receiver LO doubler is used and 4.35 dB when the high-band LO is directly driven.

Figure 11. Block Diagram of the High-Band Receiver Section

TRF1500 Integrated Dual-Band RF Receiver User’s Guide

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Texas Instruments TRF1500 manual

Contents

Evaluation Board Documentation Wireless Communications Business UnitDigital Signal Processing Solutions July APPLICATION BRIEF SWRA004AIMPORTANT NOTICE TRADEMARKS HP SUPPORT LINE PIC TELEPHONEPIC FAX PIC emailContents Low-Bandand High-BandTransmit Figures TablesAbstract Power Amp Product SupportSwitches SWRA004ARelated Documentation World Wide WebIntroduction External Components Design ConsiderationsBoard Design and Impedance Matching TRF 1500 Dual-BandReceiver Figure 1. TRF1500 Dual-BandReceiver Block DiagramName Table 1. Pin DescriptionsPin Number DescriptionPage Control Code TRF1500 Control StateActive Circuits Page Low-BandLNA Turn on Time Low-BandLNAFigure 3. Voltage Divider at Low-BandLNA Input Low-BandLNA Input Figure 4. Low-BandLNA Input ConfigurationLow-BandLNA Output Surface Acoustic Wave SAW Filter Figure 5. Low-BandLNA Output ConfigurationFigure 6. SAW Filter Insertion Loss Low-BandMixer Figure 7. Low-BandMixer RF Input ConfigurationLow-BandMixer RF Input Low-BandMixer LO Input Figure 8. Low-BandMixer LO Input ConfigurationLow-BandIF Output Figure 9. Low-BandIF Output Configuration Low-BandLO Buffer Amplifier OutputSWRA004A Low-BandCascaded Test Guide LOW-BandCascaded Power Conversion GainLow-BandCascaded Power Conversion Gain Reduction Low-BandCascaded Noise Figure Transmission line, filter and circulator Low-BandCascaded RF Input Return Loss Low-BandCascaded LO Input Return LossLOW BAND LO Buffer Output Power Low-Band Power Leakage LO In to RF InControl state SEE APPENDIX A TEST BENCH SETUPS Low-BandCascaded 1dB RF Input Compression Point Low-BandCascaded 1dB Blocking Point Page High-BandRF Input Figure 12. High-BandRF Input ConfigurationHigh-BandLO Input Note To use the high-bandLO input, remove C40 and Figure 15. High-BandIF Output Configuration High-BandIF OutputHigh-BandLO Buffer Amplifier Output High-BandCascaded Test Guide High-BandCascaded Power Conversion Gain6Calculate the Cascaded Gain as High-BandCascaded Image Rejection High-BandCascaded Noise Figure High-BandCascaded RF Input Return Loss High-Band LO Buffer Output Power High-BandCascaded Power Leakage LO In to RF In High-BandCascaded 1dB Input Compression Point High-BandCascaded 2X2 Spur Performance High Band 3X3 Spur Performance Low- and High-BandTransmit Mixer Low-Bandand High-BandTransmitLow-Bandand High-BandTransmit Mixer RF Input Low- and High-BandTransmit Mixer IF Output Low-BandTransmit Mixer Test Guide Low-BandTransmit Mixer Power Conversion GainLow-BandTransmit Mixer Noise Figure Low-BandTransmit Mixer Input Return Loss 4Set the network analyzer to measure S11 4Measure the TX leakage power Control state SEE APPENDIX A TEST BENCH SETUPS Control state SEE APPENDIX A TEST BENCH SETUPS High-BandTransmit Mixer Test Guide Low-BandLNA Gain Low-BandLNA Stand-AloneTest GuideLow-BandLNA Input Return Loss Low-BandLNA Isolation Low-BandLNA Output Return LossLow-BandLNA 1dB Input Compression Point Low-BandLNA Noise Figure 5To calibrate the NF Meter 8Calculate the Intermodulation Suppression as Low-BandReceiver Mixer Stand-AloneTest Guide Low-BandReceiver Mixer Power Conversion GainLow-BandReceiver Mixer Input Return Loss Low-BandReceiver Mixer Noise Figure aOn the front panel, press the ENR button 10Measure the Noise Figure Control state SEE APPENDIX A TEST BENCH SETUPS Suppression/2 + RF Pin Input Third-OrderIntercept = IntermodulationSWRA004A Appendix A Test Bench Configuration Figure 22. Test Bench Setup Noise Figure