MGA86576 HP [Agilent(Hewlett-Packard)], MGA86576 Datasheet - Page 4

• Manufacturer Part Number: MGA86576
• Description: 1.5 - 8 GHz Low Noise GaAs MMIC Amplifier
• Manufacturer: HP [Agilent(Hewlett-Packard)]

MGA-86576 Typical Noise Parameters
T
[3]
MGA-86576 Applications
Information
Introduction
The MGA-86576 is a high gain,
broad band, low noise amplifier.
The use of plated through holes or
an equivalent minimal inductance
grounding technique placed
precisely under each ground lead
at the device is highly recom-
mended. A minimum of two
plated through holes under each
ground lead is preferred with four
being highly suggested. A long
ground path to pins 2 and 4 will
add additional inductance which
can cause gain peaking in the 2 to
4 GHz frequency range. This can
also be accompanied by a
decrease in stability. A suggested
Figure 7. Layout for MGA-86576
Demonstration Amplifier. PCB
dimensions are 1.18 inches wide by
1.30 inches high.
C
Reference plane taken at point where leads meet body of package.
= 25 C, Z
Frequency
GHz
1.0
1.5
2.5
4.0
6.0
8.0
o
= 50 , V
NF
d
dB
2.1
1.6
1.5
1.6
1.8
2.1
= 5 V
o
Mag.
0.56
0.54
0.47
0.38
0.28
0.22
layout is shown in Figure 7. The
circuit is designed for use on
0.031 inch thick FR-4/G-10 epoxy
glass dielectric material.
Printed circuit board thickness is
also a major consideration.
Thicker printed circuit boards
dictate longer plated through
holes which provide greater
undesired inductance. The para-
sitic inductance associated with a
pair of plated through holes
passing through 0.031 inch thick
printed circuit board is
approximately 0.1 nH, while the
inductance of a pair of plated
through holes passing through
0.062 inch thick board is about
0.2 nH. Hewlett-Packard does not
Figure 8. Demonstration Amplifier Schematic.
opt
50
27 pF
Ang.
107
27
31
40
54
77
[3]
50
6-231
,
L1
100-1000 pF
1
R
N
0.43
0.40
0.36
0.32
0.28
0.25
/50
4
2
C1
R1
3
10-100
V
HIGH Z
dd
50
recommend using the MGA-86576
MMIC on boards thicker than
0.040 inch.
The effects of inductance asso-
ciated with the board material are
easily analyzed and very predict-
able. As a minimum, the circuit
simulation should consist of the
data sheet S-Parameters and an
additional circuit file describing
the plated through holes and any
additional inductance associated
with lead length between the
device and the start of the plated
through hole. To obtain a
complete analysis of the entire
amplifier circuit, the effects of the
input and output microstriplines
and bias decoupling circuits
should be incorporated into the
circuit file.
Device Connections V
Output (Pin 3)
RF and DC connections are
shown in Figure 8. DC power is
provided to the MMIC through the
same pin used to obtain RF
output. A 50
used to connect the device to the
following stage or output
connector. A bias decoupling
network is used to feed in V
27 pF
50
microstripline is
d
and RF
dd