RF3330 datasheet(8/10 Pages) RFMD

8 / 10 page

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RF3330

Rev A4 060908

Output

On the output, the losses due to the resistive matching

pad must also be calibrated out of the setup. Because

of the 1:1 transformer, the spectrum analyzer appears

as a 50

Ω resistor in parallel with this circuit (see Figure

2). Equation 4 illustrates the calculation necessary to

obtain the amount of loss due to this matching circuit.

The balun also has an additional 0.5dB to 1.0dB of

loss, which is added in to the overall output losses.

This was verified with a spectrum analyzer probe. The

offset used in the test setup is 32.5dB on the spectrum

analyzer.

Resistive Pad Loss=

20*log(25/(470+25+470))=-31.7dBEq. 4

3330410 Evaluation Board

1:1

Transformer

Frequency =

1 MHz to

150 MHz

Spectrum Analyzer

Resistive

Match

Mini-Circuits

ZMSCJ-2-1

Divider

Frequency =

1 MHz to

150 MHz

Frequency =

1 MHz to

150 MHz

Signal Generator

RF3330

Figure 1. RF3330 Test Setup

470

Figure 2. Equivalent Output Circuit

RF3330 Datasheet(PDF) 8 Page - RF Micro Devices