Texas Instruments TRF1500 manual High-Band RF Input, High-Band LO Input

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SWRA004A

High-Band RF Input

Figure 12 details the high-band RF input configuration. The cascaded noise figure and input return loss performance of the high-band receiver section is determined primarily by the input matching network. The input matching network is designed for optimum noise figure performance, while maintaining good input return loss. A low-pass shunt-C (C20) series-L (L20) network is used for the input impedance matching. The series capacitor (C29) on the input port is used for dc blocking purposes. The end- user can optimize the input matching network for better input return loss but obtaining a better input match may degrade the overall cascaded noise figure performance.

Figure 12. High-Band RF Input Configuration

High-Band LO Input

The high-band LO signal is fed through a buffer amplifier into a differential quadrature generator, which is realized using a polyphase network. The signals generated by the polyphase network are used to drive two mixers which are injected with a common RF signal. The IF signals out of these mixers will have a 180° phase shift of the image frequency as compared to the wanted RF frequency. As a result of this 180° phase shift, the IF signals at the image frequency will cancel in the quadrature combiner. The IF signal at the desired frequency will add in the quadrature combiner.

The TRF1500 offers several methods for providing high-band LO drive. The high-band LO terminal may be directly driven either single-ended or differentially. Alternately, the high-band LO terminal may be driven by using the low-band LO output and the integrated frequency doubler.

36	TRF1500 Integrated Dual-Band RF Receiver User’s Guide

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Contents TRF1500 Integrated Dual-Band RF Receiver User’s Guide Important Notice Trademarks PIC Telephone Contents Appendix a Test Bench Configuration Tables FiguresAbstract TRF1500 Integrated Dual-Band RF Receiver User’s GuideIngl E Chip Anal OG AS E B Product SupportWorld Wide Web Related DocumentationIntroduction Board Design and Impedance Matching Design ConsiderationsExternal Components TRF 1500 Dual-Band Receiver TRF1500 Dual-Band Receiver Block DiagramPin Number Name Description Pin DescriptionsStrong Signal Control State and the Corresponding Active Circuits TRF1500 Control StateCascaded Block Diagram of the Low-Band Receiver Section Low-Band LNA Turn on Time Low-Band LNALow-Band LNA Output Low-Band LNA InputSurface Acoustic Wave SAW Filter Low-Band LNA Output ConfigurationLow-Band Mixer RF Input Low-Band MixerLow-Band if Output Low-Band Mixer LO InputLow-Band LO Buffer Amplifier Output Low-Band if Output ConfigurationLow-Band Buffer Amplifier Output Configuration LB LNA, LB Mixer, SAW Filter, and LB if Amp Parameters LOW-Band Cascaded Power Conversion GainLow-Band Cascaded Test Guide Low-Band Cascaded Power Conversion Gain Reduction Low-Band Cascaded Noise Figure TRF1500 Integrated Dual-Band RF Receiver User’s Guide Low-Band Cascaded LO Input Return Loss Low-Band Cascaded RF Input Return LossLow-Band Power Leakage LO In to RF LOW Band LO Buffer Output PowerLow-Band Cascaded Third Order Input Intercept Point IIP3 Low-Band Cascaded 1dB RF Input Compression Point Low-Band Cascaded 1dB Blocking Point Block Diagram of the High-Band Receiver Section High-Band LO Input High-Band RF InputHigh-Band LO Frequency Doubler Driven Configuration High-Band if Output High-Band if Output ConfigurationHigh-Band LO Buffer Amplifier Output High-Band LO Buffer Amplifier Output ConfigurationHB LNA, HB mixer, HB if amp High-Band Cascaded Power Conversion GainHigh-Band Cascaded Test Guide High-Band Cascaded Power Conversion Gain Reduction High-Band Cascaded Image Rejection High-Band Cascaded Noise Figure High-Band Cascaded RF Input Return Loss High-Band LO Buffer Output Power High-Band Cascaded Third Order Input Intercept Point IIP3 High-Band Cascaded Power Leakage LO In to RFHigh-Band Cascaded 1dB Input Compression Point High-Band Cascaded 2X2 Spur Performance High Band 3X3 Spur Performance Low-Band and High-Band Transmit Mixer RF Input Low-Band and High-Band TransmitLow- and High-Band Transmit Mixer Low- and High-Band Transmit Mixer if Output Configuration Low- and High-Band Transmit Mixer RF Input ConfigurationLow-Band Transmit Performance Parameters Low-Band Transmit Mixer Power Conversion GainLow-Band Transmit Mixer Test Guide Low-Band Transmit Mixer Noise Figure Low-Band Transmit Mixer Input Return Loss Low-Band Transmit Mixer Power Leakage TX In to LO Low-Band Transmit Mixer Power Leakage LO In to TXLow-Band Transmit Mixer 1dB Input Compression Point See Appendix a Test Bench Setups See Appendix a Test Bench Setups High-Band Transmit Mixer Performance Parameters High-Band Transmit Mixer Test GuideLow-Band LNA Parameters Low-Band LNA Stand-Alone Test GuideLow-Band LNA Gain Low-Band LNA Input Return LossLow-Band LNA 1dB Input Compression Point Low-Band LNA Output Return LossLow-Band LNA Isolation Low-Band LNA Noise Figure Low-Band LNA Third Order Input Intercept Point IIP3 TRF1500 Integrated Dual-Band RF Receiver User’s Guide Low-Band Receiver Mixer Parameters Low-Band Receiver Mixer Power Conversion GainLow-Band Receiver Mixer Stand-Alone Test Guide Low-Band Receiver Mixer Input Return Loss Low-Band Receiver Mixer Noise Figure Low-Band Receiver Mixer Power Leakage LO In to RFTRF1500 Integrated Dual-Band RF Receiver User’s Guide Low-Band Receiver Mixer 1dB RF Input Compression Point 12.2 11.4 10.4 ←1dB Compression Point TRF1500 Integrated Dual-Band RF Receiver User’s Guide Appendix a Test Bench Configuration Test Bench Setup Noise Figure Test Bench Setup Power Leakage RF In to LO In Measurements Test Bench Setup LNA 1dB Input Compression Point