RF2174 datasheet(12/16 Pages) RFMD

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RF2174

Rev A8 DS060918

7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical

support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.

Typical Test Setup

Power Supply

V- S- S+ V+

10dB/5W

3dB

RF Generator

Spectrum

Analyzer

Buffer

x1 OpAmp

Pulse

Generator

A buffer amplifier is recommended because the current into

the VAPC changes with voltage. As an alternative, the voltage

may be monitored with an oscilloscope.

Notes about testing the RF2174

The test setup shown above includes two attenuators. The 3dB pad at the input is to minimize the effects that the switching

of the input impedance of the PA has on the signal generator. When VAPC is switched quickly, the resulting input impedance

change can cause the signal generator to vary its output signal, either in output level or in frequency. Instead of an attenuator

an isolator may also be used. The attenuator at the output is to prevent damage to the spectrum analyzer, and should be able

to handle the power.

It is important not to exceed the rated supply current and output power. When testing the device at higher than nominal sup-

ply voltage, the VAPC should be adjusted to avoid the output power exceeding +36dBm. During load-pull testing at the output

it is important to monitor the forward power through a directional coupler. The forward power should not exceed +36dBm,

and VAPC needs to be adjusted accordingly. This simulates the behavior for the power control loop in this respect. To avoid

damage, it is recommended to set the power supply to limiting the current during the burst, not to exceed the maximum cur-

rent rating.

RF2174 Datasheet(PDF) 12 Page - RF Micro Devices