MGA-52543 データシートの表示（PDF） - HP => Agilent Technologies
部品番号
コンポーネント説明
メーカー
MGA-52543 Datasheet PDF : 15 Pages
| |||
Final Note on Performance
An effective way of lowering
production costs is to replace
lumped elements with microstrip
components. The inductors for the
input and output match maybe
printed elements as well as
lumped elements. To save board
space the use of lumped elements
at lower frequencies is recom-
mended. The effects of leaving the
MGA-52543 unmatched can have a
negative effect on the perfor-
mance of the device. Gain and
OIP3 performance are greatly
reduced by using the device
unmatched. Table 4 gives typical
performance at 1900 MHz for the
MGA-52543 in an unmatched
configuration using the evaluation
board shown in Figure 5.
Test
Unmatched Matched
Results
Results
Gain
OIP3
IIP3
P1dB
Input RL
Out RL
12.5 dB
30.0 dBm
17.5 dBm
17.0 dBm
5.1 dB
10.2 dB
14.3 dB
31.8 dBm
17.5 dBm
17.5 dBm
10.2 dB
21.9 dB
Table 4. Results of Matching Circuits on
MGA-52543.
Hints and Troubleshooting
• Oscillation
Unconditional stability of the
MGA-52543 is dependent on
having very good grounding.
Inadequate device grounding or
poor PCB layout techniques could
cause the device to be potentially
unstable.
Even though a design may be
unconditionally stable (K > 1 and
B1 > 0) over its full frequency
range, other possibilities exist that
may cause an amplifier circuit to
oscillate. One thing to check for, is
feedback in bias circuits. It is
important to capacitively bypass
the connections to active bias
circuits to ensure stable operation.
In multistage circuits, feedback
through bias lines can also lead to
oscillation.
Components of insufficient quality
for the frequency range of the
amplifier can sometimes lead to
instability. Also, component values
that are chosen to be much higher
in value than is appropriate for the
application can present a problem.
In both of these cases, the compo-
nents may have reactive parasitics
that make their impedances very
different than expected. Chip
capacitors may have excessive
inductance, or chip inductors can
exhibit resonances at unexpected
frequencies. For example it is a
good idea not to use the same
type/value of inductors for L1 and
L2. It can be shown that if the self-
resonant frequency of the induc-
tors used on the input and the
output of the MGA-52543 are the
same, then the device can be left
unterminated at high frequencies.
• A Note on Supply Line
Bypassing
Multiple bypass capacitors are
normally used throughout the
power distribution within a
wireless system. Consideration
should be given to potential
resonances formed by the combi-
nation of these capacitors and the
inductance of the DC distribution
lines. The addition of a small value
resistor in the bias supply line
between bypass capacitors will
often de-Q the bias circuit and
eliminate resonance effects.
Statistical Parameters
Several categories of parameters
appear within this data sheet.
Parameters may be described with
values that are either “minimum or
maximum,” “typical,” or “standard
deviations.”
The values for parameters are
based on comprehensive product
characterization data, in which
automated measurements are
made on of a minimum of 400
parts taken from three non-
consecutive process lots of
semiconductor wafers. The data
derived from product character-
ization tends to be normally
distributed, e.g., fits the standard
bell curve.
Parameters considered to be the
most important to system perfor-
mance are bounded by minimum
or maximum values. For the
MGA-52543, these parameters are:
Input IP3 (IIP3test), Gain (Gtest),
Noise Figure (NFtest), and Device
Current (Id). Each of the guaran-
teed parameters is 100% tested as
part of the manufacturing process.
Values for most of the parameters
in the table of Electrical Specifica-
tions that are described by typical
data are the mathematical mean
(µ), of the normal distribution
taken from the characterization
data. For parameters where
measurements or mathematical
averaging may not be practical,
such as S-parameters or Noise
Parameters and the performance
curves, the data represents a
nominal part taken from the
center of the characterization
distribution. Typical values are
intended to be used as a basis for
electrical design.
To assist designers in optimizing
not only the immediate amplifier
circuit using the MGA-52543, but
to also evaluate and optimize
trade-offs that affect a complete
wireless system, the standard
deviation (µ) is provided for many
of the Electrical Specifications
parameters (at 25°C) in addition
to the mean. The standard devia-
tion is a measure of the variability
about the mean. It will be recalled
that a normal distribution is
completely described by the mean
and standard deviation.
13
Share Link: 