Texas Instruments TRF1500 Low-Band and High-Band Transmit, Low- and High-Band Transmit Mixer

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SWRA004A

Low-Band and High-Band Transmit

Low- and High-Band Transmit Mixer

Figure 17 details the block diagram of the transmit mixer. The TRF1500 provides a transmit mixer for down converting the system transmit signal (low-band or high-band) to a common IF for loop-back testing. The LO input for this mixer can be selected from either the low-band LO input or the high-band LO input by means of the digital control. The RF input of the transmit mixer provides a broad-band 200Ω differential input impedance over a band of 800 MHz to 2GHz and thus requires minimal external matching.

The mixer is a double-balanced Gilbert cell design with open collector outputs. The Gilbert cell structure was implemented for its robust isolation and harmonic suppression characteristics.

Figure 17. Transmit Mixer Block Diagram

Low-Band and High-Band Transmit Mixer RF Input

Figure 18 details the transmit mixer RF input configuration. The transmit mixer can be either driven single-ended or differentially. For evaluation purposes, a 4:1 transformer balun is used on the EVM to drive the transmit mixer single-ended. The input requires very little external matching. A shunt capacitor (C35) near the input port (J30) and a shunt capacitor (C36) near the transformer balun (T30) are the only input impedance matching components required.

50	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 External Components Design ConsiderationsBoard Design and Impedance Matching 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 Low-Band Cascaded Test Guide LOW-Band Cascaded Power Conversion GainLB LNA, LB Mixer, SAW Filter, and LB if Amp Parameters 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 ConfigurationHigh-Band Cascaded Test Guide High-Band Cascaded Power Conversion GainHB LNA, HB mixer, HB if amp 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- and High-Band Transmit Mixer Low-Band and High-Band TransmitLow-Band and High-Band Transmit Mixer RF Input Low- and High-Band Transmit Mixer if Output Configuration Low- and High-Band Transmit Mixer RF Input ConfigurationLow-Band Transmit Mixer Test Guide Low-Band Transmit Mixer Power Conversion GainLow-Band Transmit Performance Parameters 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 Gain Low-Band LNA Stand-Alone Test GuideLow-Band LNA Input Return Loss Low-Band LNA ParametersLow-Band LNA Isolation Low-Band LNA Output Return LossLow-Band LNA 1dB Input Compression Point 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 Stand-Alone Test Guide Low-Band Receiver Mixer Power Conversion GainLow-Band Receiver Mixer Parameters 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