基于BLF888設(shè)計(jì)的500W RF廣播發(fā)射方案

NXP 公司的BLF888是500W LDMOS RF功率晶體管，用于廣播發(fā)射和工業(yè)應(yīng)用。在UHF頻帶470 MHz 到860 MHz可提供平均功率110W，峰值包絡(luò)功率500W，功率增益19dB，漏極效率46%，VDS 電壓50 V，漏極靜態(tài)電流1.3A。本文主要介紹了BLF888主要特性和優(yōu)勢(shì)，AB類共源寬帶放大器電路和元件列表以及PCB布局圖和元件布局圖。

A 500 W LDMOS RF power transistor for broadcast transmitter applications and industrial applications. The transistor is optimized for digital applications and can deliver 110 W average DVB-T broadband over the full UHF band from 470 MHz to 860 MHz. The excellent ruggedness of this device makes it ideal for digital transmitter applications.

BLF888主要特性和優(yōu)勢(shì)：
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2-Tone performance at 860 MHz, a drain-source voltage VDS of 50 V and a quiescent drain current IDq = 1.3 A:
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Peak envelope power load power = 500 W
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Power gain = 19 dB
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Drain efficiency = 46 %
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Third order intermodulation distortion = 32 dBc
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DVB performance at 858 MHz, a drain-source voltage VDS of 50 V and a quiescent drain current IDq = 1.3 A:
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Average output power = 110 W
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Power gain = 19 dB
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Drain efficiency = 31 %
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Shoulder distance = 31 dBc (4.3 MHz from center frequency)
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Integrated ESD protection
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Advanced flange material for optimum thermal behavior and reliability
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Excellent ruggedness
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High power gain
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High efficiency
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Designed for broadband operation (470 MHz to 860 MHz)
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Excellent reliability
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Internal input matching for high gain and optimum broadband operation
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Easy power control
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Compliant to Directive 2002/95/EC, regarding Restriction of Hazardous Substances (RoHS)

BLF888應(yīng)用：
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Communication transmitter applications in the UHF band
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Industrial applications in the UHF band


圖1。BLF888 AB類共源寬帶放大器電路

AB類共源寬帶放大器元件列表：




圖2。AB類共源寬帶放大器PCB布局圖

圖3。AB類共源寬帶放大器元件布局圖