RF5110
Typical Test Setup
Power Supply
V- V+ S+ S-
RF Generator
Spectrum
Analyzer
3dB
10dB/5W
Buffer
x1 OpAmp
Pulse
Generator
A buffer amplifier is recommended because the current into the V
APC
changes with voltage. As an alternative, the voltage may be
monitored with an oscilloscope.
Notes about testing the RF5110
The test setup shown above includes two attenuators. The 3dB pad at the input is to minimize the effect on the signal genera-
tor as a result of switching the input impedance of the PA. When V
APC
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 sized
accordingly 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 supply
voltage, the V
APC
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
V
APC
needs to be adjusted accordingly. This simulates the behavior for the power control loop. To avoid damage, it is recom-
mended to set the power supply to limit the current during the burst not to exceed the maximum current rating.
Rev A0 DS050318
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical
support, contact RFMD at (+1) 336-678-5570 or sales-support@rfmd.com.
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