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MRFE6VP61K25H MRFE6VP61K25HS FM Broadcast

RF Reference Design Data

Freescale Semiconductor

RF Power Reference Design Library

FM Broadcast Reference Design

High Ruggedness N--Channel Enhancement--Mode

Lateral MOSFETs

Reference Design Characteristics

The MRFE6VP61K25H/HS are versatile devices and are well suited for a

wide range of applications . They are capable of delivering 1.2 kW under

continuous wave test s ignaling as a result of their high efficienc y and low

thermal resistance. This document focuses on FM broadcast radio applications

for both analog and complex modulation waveforms.

 Frequency Band: 87.5--108 MHz

 Output Power: 1100 Watts CW

 Supply Voltage: 50 Vdc

 Power Gain (Typ): 25 dB

 Drain Efficiency (Min): 79% (at fundamental frequency)

The MRFE6VP61K25H/HS products are enhanced ruggedness 50 volt

LDMOS power transistors that can operate in harsh environments and in highly

mismatched applications (within the limit of maximum junction temperature).

These parts are designed for high voltage operation and are fabricated using

Freescale’s very high voltage 6th generation (VHV6E) platform.

FM BROADCAST REFERENCE DESIGN

This reference design is designed to demonstrate the RF

performance characteristics of the MRFE6VP61K25H/HS

devices when applied to the 87.5--108 MHz FM broadcast

frequency band. The reference design is tuned for

performance at 1100 watts CW output power , V

=50volts

and I

= 200 mA.

REFERENCE DESIGN LIBRARY TERMS

AND CONDITIONS

Freescale is pleased to make this reference design

available for your use in development and testing of your

own product or products. The reference design contains an

easy--to--copy, fully functional amplifier design. It consists of

“no tune” distributed element matching circuits designed to

be as small as possible, and is designed to be used as a

“building block” by our customers.

HEATSINKING

When operating this fixture it is critical that adequate heat-

sinking is provided for the device. Excessive heating of the

device may prevent duplication of the included measurements

and/or destruction of the device.

Figure 1. FM Broadcast Reference Design Fixture

Available at http://www.freescale.com. Go to Support/Software & Tools/

Additional Resources/Reference Designs/Networking

Rev. 1.1, 6/201 1

Freescale Semiconductor

Technical Data

 REFERENCE DESIGN IN 1st REVIEW -- 06/03/11

MRFE6VP61K25H

MRFE6VP61K25HS

FM Broadcast

87.5--108 MHz, 1100 W CW, 50 V

FM BROADCAST

REFERENCE DESIGN

OUTPUT

INPUT

BIAS

M=Match

 Freescale Semiconductor, Inc., 2011.

ll rights reserved.

Summary of content (14 pages)

PAGE 1
Freescale Semiconductor Technical Data REFERENCE DESIGN IN 1st REVIEW -- MRFE6VP61K25H MRFE6VP61K25HS FM Broadcast RF Power Reference Design Library FM Broadcast Reference Design Reference Design Characteristics The MRFE6VP61K25H/HS are versatile devices and are well suited for a wide range of applications. They are capable of delivering 1.2 kW under continuous wave test signaling as a result of their high efficiency and low thermal resistance.
PAGE 2
MEASUREMENTS f = 108 MHz 98 MHz 32 80 30 70 28 60 27 50 87.5 MHz 98 MHz 26 Gps VDD = 50 V IDQ = 200 mA 25 24 100 200 300 400 500 600 700 40 30 90 80 ηD 28 70 26 60 Gps 24 Pout = 1100 W VDD = 50 V IDQ = 200 mA 22 20 86 20 800 900 1000 1100 1200 50 88 90 92 40 94 96 98 ηD, DRAIN EFFICIENCY (%) Gps, POWER GAIN (dB) 87.5 MHz 90 Gps, POWER GAIN (dB) ηD 30 29 108 MHz ηD, DRAIN EFFICIENCY (%) 31 30 100 102 104 106 108 110 Pout, OUTPUT POWER (WATTS) Air--Cooled, CW, 87.
PAGE 3
AMPLIFIER DESIGN MATCHING NETWORK FIXTURE IMPEDANCE As a first order approximation, the typical maximum efficiency impedance point corresponds to a 25% power degradation from the maximum P3dB impedance. The maximum output power impedance value on this device corresponds to a 1.25 kW output capability from 87.5--108 MHz. This puts the targeted P1dB compression value at 800 watts of output power total, or 400 watts per side.
PAGE 4
CIRCUIT DESCRIPTION C1 C3 B1 VGS R1 RF INPUT L2 T1 L1 L3 C2 C15 C16 C17 C19 C18 VDD B2 COAX1 C7 C8 RF OUTPUT COAX3 C9 C4 C5 C10 C11 COAX2 B3 C22 C12 C23 C24 C21 C20 VDD Figure 6.
PAGE 5
COAX1 C15 C16 C1 C19 C18 + + C17 B1 L2 T1 L3 C2 CUT OUT AREA R1 L1 COAX3 L4 C3 C7 C8 C9 C4 C10 C11 + + C21 C20 C24 MRFE6VP61K25H Rev. 1 C22 C5 C12 L5 C23 Note: Component numbers C6, C13 and C14 are not used. COAX2 Figure 7. FM Broadcast Reference Design Component Layout Table 4. FM Broadcast Reference Design Component Designations and Values Part Description Part Number Manufacturer B1 Long Ferrite Bead 2743021447 Fair--Rite C1 6.
PAGE 6
FREESCALE RF POWER 50 V TECHNICAL ADVANTAGES 50 V Drain Voltage Enhanced ESD 1.E--02 IESD (A) The 87.5--108 MHz FM broadcast reference design fixture was designed to utilize the standard 50 volt power supply commonly used in this market. Data was collected to characterize the reference design’s output power and efficiency vs. drain voltage, as shown in Figure 8.
PAGE 7
Figure 10 shows the internal diagram of the ITC55100B tester. The tester controller activates the pulse generator to turn on the device under test (DUT) through the limiting and terminating resistor, RG, creating a very clean gate pulse waveform. This pulse waveform tests the maximum energy dissipation capability of the DUT by stressing it under various, controlled energy levels.
PAGE 8
Reliability Mean time to failure (MTTF) is defined as a 10% reduction in current handling capability on 50% of the devices within a given sample size. The primary factor in device failure is due to metal electromigration on the die surface. Once the average operating conditions for a given application are determined, then the MTTF can be calculated using the thermal resistance Rth value given in the MRFE6VP61K25H product data sheet.
PAGE 9
APPENDIX A Tuning Tips • Increasing C4 increases efficiency at the low end of the band (87.5 MHz), but there is a trade--off in power at the high end of the band. • Increasing the length of Coax3 increases efficiency at the low end of the band (87.5 MHz), but there is a trade off in efficiency and power at the high end of the band. • Make sure all the coax are measured tip to tip. • Increasing C5 increases the power, but lowers efficiency.
PAGE 10
APPENDIX B Mounting Tips The MRFE6VP61K25H/HS is packaged in the industry standard NI--1230 air cavity package which offers a standardized package for easy replacement drop in as well as outstanding thermal performance. This package can be assembled into a power amplifier system using several different mounting methods. The popular options include bolting down with screw, clamping and reflow soldering in a cavity. Freescale recommends solder reflow.
PAGE 11
APPENDIX C RF Bench Setup/Continuous Wave Performance (CW) Pin N1912 Channel A with 10 dB Attenuator ESG Generator Power Reflected HP437 with 10 dB Attenuator Narda Model 31993 50--1000 MHz Coupler VGG VDD DUT Tenuline Coaxial Attenuator Model (8329--300) 30 dB Attenuator +19 dB additional DC to 3 GHz 150 MHz LPF Power Meter N1912 Channel B Figure 14.
PAGE 12
APPENDIX D 1.929 (48.98) 8x #4--40 0.300″ deep 2.737 (69.51) 0.41 (10.41) 1.813 (46.04) 2.719 (69.07) E F A D A B D A 2.882 (73.19) A D E 0.813 (20.64) 0.140 (3.56) 1.309 (33.26) B 0.611 (15.52) F D 1.668 (42.38) 1.489 (37.83) ∅0.188 (∅4.76) 1.129 (28.69) 0.950 (24.14) B A D 0.130 (3.32) 0.125 (3.17) 4.725 (120.02) 4.499 (114.28) 2.929 (74.38) 2.283 (57.98) 1.724 (43.78) 2.134 (54.19) AA 1.929 (48.99) 1.558 (39.58) 0.929 (23.59) 0.000 (0.00) 0.00 (0.00) 0.177 (4.50) 0.
PAGE 13
REVISION HISTORY The following table summarizes revisions to this document. Revision Date Description 1 May 2011 • Table 4, Component Designations and Values, updated C17, C24 capacitor from “50 V, GRM55DR61H106KA88L, Murata” to “100 V, C5750X7S2A106MT, TDK”, 100 V part provides higher breakdown voltage capability. Corrected R1 part number from “CRCW1206110FKEA” to CRCW120611R0FKEA”. For Coax1, 2, 3, in description changed cm to inches, p. 4. 1.
PAGE 14
How to Reach Us: Home Page: www.freescale.com Web Support: http://www.freescale.com/support USA/Europe or Locations Not Listed: Freescale Semiconductor, Inc. Technical Information Center, EL516 2100 East Elliot Road Tempe, Arizona 85284 1--800--521--6274 or +1--480--768--2130 www.freescale.