1
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
Product Image
CASE 211–11, STYLE 2
Designed for broadband commercial and military applications up to
200 MHz frequency range. The high–power, high–gain and broa dband
performance of this device make possible so lid state transmitters for
FM broadcast or TV channel frequ ency bands.
N–Channel enhancement mode MOSFET
Guaranteed performance at 150 MHz, 28 V:
Output power = 80 W
Gain = 11 dB (13 dB typ.)
Efficiency = 55% min. (60% ty p.)
Low thermal resistance
Ruggedness tested at rated output po wer
Nitride passivated die for enhanced reliabilit y
Low noise figure — 1.5 dB typ at 2.0 A, 150 MHz
Excellent thermal stability; suited for Class A operation
2
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
3
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
4
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
5
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
6
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
7
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
8
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
9
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
10
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
11
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.
DESIGN CONSIDERATIONS
The MRF173 is a RF MOSFET power N–channel en-
hancement mode field–effect transistor (FET) designed for
VHF power amplifier applications. M/A-COM RF MOSFETs
feature a vertical structure wit h a planar design, thus avoi d-
ing the processing difficulties associated with V–groove
power FETs.
M/A-COM Application Note AN211A, F E Ts in Theory and
Practice, is suggested reading for those not familiar with the
construction and characteristics of FETs.
The major advantages of RF power FETs include high
gain, low noise, simple bias systems, relativ e immunity from
thermal runaway, and the ability to withstand severely mis-
matched loads without suffering damage. Po wer output can
be varied over a wide range with a low power dc control
signal, thus facilitating manual gain control, ALC and modu-
lation.
DC BIAS
The MRF173 is an enhancement mode FET and, there-
fore, does not conduct when drain voltage is applied. Drain
current flows when a positive voltage is applied to the gate.
See Figure 9 for a typical plot of drain current versus gate
voltage. RF power FETs require forward bias for optimum
performance. The value of quiescent drain current (IDQ) is
not critical for many applications. T he MRF173 was charac-
terized at IDQ = 50 mA, which is the suggested minimum
value of IDQ. For special applicati ons such as linear amplifi-
cation, IDQ may have to be selected to optimize the critical
parameters.
The gate is a dc open circuit a nd dra ws no c urrent. T here-
fore, the gate bias circuit may generally be just a simple re-
sistive divider network. Some special applications may re-
quire a more elaborate bias system.
GAIN CONTROL
Power output of the MRF173 may be controlled from its
rated value down to zero (negative gain) by varying the dc
gate voltage. This feature facilitates the design of manual
gain control, AGC/ALC and modu lation systems.
(see Figure 8.)
AMPLIFIER DESIGN
Impedance matching networks similar to those used with
bipolar VHF transistors are suitable for MRF173. See M/A-
COM Application Note AN721`, Impedance Matching Net-
works Applied to RF Power Transistors. The higher input
impedance of RF MOSFETs helps ease the task of broad-
band network design. Both small–signal scattering parame-
ters and large–signal imped ances are pr ovided. While the s–
parameters will not produce a n exact design soluti on for hig h
power operation, they do yield a good first approximation.
This is an additional adv antage of RF MOS power FETs.
12
The RF MOSFET Line
80W, 175MHz, 28V M/A-COM Products
Released - Rev. 07.07
MRF173
North America Tel: 800.366.2266 / Fax: 978.366.2266
Europe Tel: 44.1908.574.200 / Fax: 44.1908.574.300
Asia/Pacific Tel: 81.44.844.8296 / Fax: 81.44.844.8298
Visit www.macomtech.com for additional data sheets and prod uct information.
M/A-COM Technology Solutions Inc. and its affiliates reserve the right to make
changes to the product(s) or information contained herein without notice.
ADVANCED: Data Sheets contain information regarding a product M/A-COM Technology Solutions
is considering for development. Performance is based on target specifications, simulated results,
and/or prototype measurements. Commitment to develop is not guaranteed.
PRELIMINARY: Data Sheets contain information regarding a product M/A-COM Technology
Solutions has under development. Performance is based on engineering tests. Specifications are
typical. Mechanical outline has been fixed. Engineering samples and/or test data may be available.
Commitment to produce in volume is not guaranteed.