- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄376145 > MAG-725M4 (Electronic Theatre Controls, Inc.) Agilent MGA-725M4 Low Noise Amplifier with Bypass Switch In Miniature Leadless Package PDF資料下載
參數(shù)資料
| 型號： | MAG-725M4 |
| 廠商： | Electronic Theatre Controls, Inc. |
| 英文描述： | Agilent MGA-725M4 Low Noise Amplifier with Bypass Switch In Miniature Leadless Package |
| 中文描述： | 安捷倫的MGA - 725M4低噪聲放大器，具有旁路開關(guān)在微型無鉛封裝 |
| 文件頁數(shù)： | 13/21頁 |
| 文件大小： | 404K |
| 代理商： | MAG-725M4 |
Application Information:
Designing with the
MGA-725M4 RFIC
Amplifier/Bypass Switch
Description
The MGA-725M4 is a single stage
GaAs RFIC amplifier with an
integrated bypass switch. A
functional diagram of the
MGA-725M4 is shown in Figure 1.
RF
OUTPUT
AMPLIFIER
BYPASS MODE
RF
INPUT
Figure 1. MGA-725M4 Functional Diagram.
The MGA-725M4 is designed for
receivers and transmitters operat-
ing from 100 MHz to 6 GHz with
an emphasis on 800 MHz and
1.9 GHz CDMA applications. The
MGA-725M4 combines low noise
performance with high linearity to
make it especially advantageous
for use in receiver front-ends.
The purpose of the switch feature
is to prevent distortion of high
signal levels in receiver applica-
tions by bypassing the amplifier
altogether. The bypass switch can
be thought of as a 1-bit digital
AGC circuit that not only prevents
distortion by bypassing the
MGA-725M4 amplifier, but also
reduces front-end system gain by
approximately 16 dB to avoid
overdriving subsequent stages in
the receiver such as the mixer.
An additional feature of the
MGA-725M4 is the ability to
externally set device current to
balance output power capability
and high linearity with low DC
power consumption. The adjust-
able current feature of the
MGA-725M4 allows it to deliver
output power levels in excess of
+15 dBm (P
1dB
), thus extending its
use to other system application
such as transmitter driver stages.
The MGA-725M4 is designed to
operate from a +3-volt power
supply and is contained in minia-
ture Minipak 1412 package to
minimize printed circuit board
space.
LNA Application
For low noise amplifier applica-
tions, the MGA-725M4 is typically
biased in the 10–20 mA range.
Minimum NF occurs at 20 mA as
noted in the performance curve of
NF
min
vs I
d
. Biasing at currents
significantly less than 10 mA is not
recommended since the character-
istics of the device begin to
change very rapidly at lower
currents.
The MGA-725M4 is matched
internally for low NF. Over a
current range of 10–30 mA, the
magnitude of G
opt
at 1900 MHz is
typically less than 0.25 and
additional impedance matching
would only net about 0.1 dB
improvement in noise figure.
Without external matching, the
input return loss for the
MGA-725M4 is approximately 5 dB
at 1900 MHz. If desired, a small
amount of NF can be traded off
for a significant improvement in
input match. For example, the
addition of a series inductance of
2.7 to 3.9 nH at the input of the
MGA-725M4 will improve the
input return loss to grater than
10 dB with a sacrifice in NF of
only 0.1 dB.
The output of the MGA-725M4 is
internally matched to provide an
output SWR of approximately 2:1
at 1900 MHz. Input and output
matches both improve at higher
frequencies.
Driver Amplifier Applications
The flexibility of the adjustable
current feature makes the
MGA-725M4 suitable for use in
transmitter driver stages. Biasing
the amplifier at 40–50 mA enables
it to deliver an output power at
1 dB gain compression of up to
+16 dBm. Power efficiency in the
unsaturated driver mode is on the
order of 30%. If operated as a
saturated amplifier, both output
power and efficiency will increase.
Since the MGA-725M4 is internally
matched for low noise figure, it
may be desirable to add external
impedance matching at the input
to improve the power match for
driver applications. Since the
reactive part of the input of the
device impedance is capacitive, a
series inductor at the input is
often all that is needed to provide
a suitable match for many applica-
tions. For 1900 MHz circuits, a
series inductance of 3.9 nH will
match the input to return loss of
approximately 13 dB. As in the
case of low noise bias levels, the
output of the MGA-725M4 is
already well matched to 50
and
no additional matching is needed
for most applications.
When used for driver stage
applications, the bypass switch
feature of the MGA-725M4 can be
used to shut down the amplifier to
conserve supply current during
non-transmit period. Supply
current in the bypass stage is
nominally 2 mA.
Biasing
Biasing the MGA-725M4 is similar
to biasing a discrete GaAs FET.
Passive biasing of the MGA-725M4
may be accomplished by either of
two conventional methods, either
by biasing the gate or by using a
source resistor.
Gate Bias
Using this method, Pins 1 and 3 of
the amplifier are DC grounded and
a negative bias voltage is applied
to Pin 2 as shown in figure 2. This
method has the advantage of not
only DC, but also RF grounding
both of the ground pins of the
MGA-725M4. Direct RF grounding
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MAS7838S-T | SYNCHRONOUS TO ASYNCHRONOUS CONVERTER SAC CMOS |
| MAS7838 | SYNCHRONOUS TO ASYNCHRONOUS CONVERTER SAC CMOS |
| MAS7838N | SYNCHRONOUS TO ASYNCHRONOUS CONVERTER SAC CMOS |
| MAS7838S | SYNCHRONOUS TO ASYNCHRONOUS CONVERTER SAC CMOS |
| MAU112 | 1 Watt Ultra Miniature SIP DC/DC Converters (Single and Dual Outputs) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MAG7A | 制造商:APEM 功能描述: |
| MAG-8-7121 | 制造商:ELECTRIX INC 功能描述:Magnifier; Mag-8; 8 Diopter; 3; Zinc; 22 W; Fluorescent; 9 ft.; UL Listed |
| MAG-8-7426 | 制造商:ELECTRIX INC 功能描述:Magnifier, Mag-8, 8 Diopter, 3, Zinc, 22 W, Fluorescent, 9 ft., UL Listed |
| MAG90X95 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:COMPLIMENTARY PAIR DUAL CHANNEL POWER MOSFET |
| MAG9412 | 制造商:TT Electronics/ Semelab 功能描述:TRANS,AUDIO,PNP,230V,30A,TO-264 制造商:SEMELAB 功能描述:TRANS,AUDIO,PNP,230V,30A,TO-264; Transistor Polarity:PNP; Collector Emitter Voltage V(br)ceo:-230V; Transition Frequency Typ ft:60MHz; Power Dissipation Pd:400W; DC Collector Current:-30A; DC Current Gain hFE:50; No. of Pins:3 ;RoHS Compliant: Yes |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。