MAX2023_1中文资料(2)

MAX2023 Evaluation KitEvaluates: MAX2023

1)Calibrate the power meter. For safety margin, use a

power sensor rated to at least +20dBm, or usepadding to protect the power head as necessary.2)Connect a 3dB pad to the DUT end of the RF signal

generators’ SMA cable. This padding improvesVSWR and reduces the errors due to mismatch.3)Use the power meter to set the RF signal generators

according to the following:

LO signal source: 0dBm into DUT at 1850MHz(this is approximately 3dBm before the 3dB pad).Use an oscilloscope to calibrate the baseband I/Qdifferential inputs to the following:

Use a signal source where I+, I-, Q+, and Q-are all 50 single-ended outputs. Load the I+/I-ports and Q+/Q- ports with 50 differentialloads. Set the voltage across the 50 differen-tial loads to be 2.7VP-Pdifferential. Remove the50 differential loads. Note that the DUT’s I+/I-and Q+/Q- port impedances will provide the differential loading in Step 10.

The MAX2023 EV kit is fully assembled and factory test-ed. Follow the instructions in the Connections andSetupsection for proper device evaluation as anupconverter.

Test Equipment Required

This section lists the recommended test equipment toverify the operation of the MAX2023 as an upconverter.It is intended as a guide only, and substitutions may bepossible.

One DC supply capable of delivering +5.0V and

350mA

One low-noise RF signal generator capable of deliv-ering 10dBm of output power in the 1GHz to 3GHzfrequency range (i.e., HP 8648)

One I/Q generator capable of producing two differ-ential 1MHz sine waves, 90°out-of-phase with eachother, with a 2.7VP-Pdifferential amplitude

One quad-channel oscilloscope with a 100MHzminimum bandwidth

Low-capacitance oscilloscope probes

One RF spectrum analyzer with a 100kHz to 3GHzfrequency range (HP 8561E)One RF power meter (HP 437B)One power sensor (HP 8482A)

4)Disable the signal generator outputs.

5)Connect the I/Q source to the differential I/Q ports.6)Connect the LO source to the EV kit LO input.7)Measure the loss in the 3dB pad and cable that will be

connected to the RF port. Losses are frequencydependent, so test this at 1850MHz (the RF frequen-cy).Use this loss as an offset in all outputpower/gain calculations.8)Connect this 3dB pad to the EV kit’s RF port con-nector and connect a cable from the pad to thespectrum analyzer.9)Set DC supply to +5.0V, and set a current limit

around 350mA, if possible. Disable the output volt-age and connect the supply to the EV kit (throughan ammeter, if desired). Enable the supply.Readjust the supply to get +5.0V at the EV kit. Avoltage drop occurs across the ammeter when thedevice is drawing current.

10)Enable the LO and the I/Q sources.

Connections and Setup

This section provides a step-by-step guide to testing thebasic functionality of the EV kit as an upconverter. As ageneral precaution to prevent damaging the outputs bydriving high VSWR loads, do not turn on DC power orRF signal generators until all connections are made.This upconverter procedure is general for operationwith an I/Q baseband input signal at 1MHz. Choose thetest frequency based on the particular system’s fre-quency plan and adjust the following procedureaccordingly. See Figure 2 for the test setup diagram.

Testing the Direct Upconverter

Adjust the center and span of the spectrum analyzer to1850MHz and 5MHz, respectively. The LO leakageappears at 1850MHz and there are two sidebands at1849MHz and 1851MHz (LSB and USB). One of thesidebands is the selected RF signal, while the second isthe image. Depending on whether the Q channel is 90degrees advanced or 90 degrees delayed from the I channel determines which sideband is selected and

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