MGA-82563-TR1G Datasheet, PDF (9/11 Pages) AVAGO TECHNOLOGIES LIMITED – MGA-82563 0.1– 6 GHz 3 V, 17 dBm Amplifier

22
20
Power
18
16
14
Gain
12
10
8
6
4
NF
2
0
0
1
2
3
4
SUPPLY VOLTAGE (V)
Figure 19. Gain, Noise Figure, and Output Power vs. Supply Voltage.
There are several means of biasing the MGA-82563 at
3 volts in systems that use higher power supply voltages.
The simplest method, shown in Figure 20a, is to use a
series resistor to drop the device voltage to 3 volts. For
example, a 24 Ω resistor will drop a 5-volt supply to 3
volts at the nominal current of 84 mA. Some variation in
performance could be expected for this method due to
variations in current within the specified 63 to 101 mA
min/max range.
+5 V
+5 V
+5 V
of less dependency on current variation in the amplifiers
since the forward voltage drop of a diode is somewhat
current independent.
Reverse breakdown diodes (e.g., Zener diodes) could
also be used as in Figure 20c. However, care should be
taken to ensure that the noise generated by diodes in
either Zener or reverse breakdown is adequately filtered
(e.g., bypassed to ground) such that the diode’s noise is
not added to the amplifier’s signal.
Note that the voltage-dropping component in each of
these three methods must be able to safely dissipate up
to 200 mW.
SOT-363 PCB Footprint
A recommended PCB pad layout for the miniature SOT-
363 (SC-70) package used by the MGA-82563 is shown in
Figure 21 (dimensions are in inches). This layout provides
ample allowance for package placement by automated
assembly equipment without adding parasitics that
could impair the high frequency RF performance of the
MGA-82563. The layout is shown with a nominal SOT-363
package footprint superimposed on the PCB pads.
24 Ω _Silicon
Diodes
Zener
Diode
0.026
(a)
(b)
(c)
Figure 20. Biasing From Higher Supply Voltages.
A second method illustrated in Figure 20b, is to use for-
ward-biased diodes in series with the power supply. For
example, three silicon diodes connected in series will
drop a 5-volt supply to approximately 3 volts.
The use of the series diode approach has the advantage
0.039
0.079
0.018
Dimensions in inches.
Figure 21. Recommended PCB Pad Layout for Avago’s SC70 6L/SOT-363 Products.
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