基于BLF888设计的500W RF广播发射方案

基于BLF888设计的500W RF广播发射方案

NXP 公司的BLF888是500W LDMOS RF功率晶体管，用于广播发射和工业应用。在UHF频带470 MHz 到860 MHz可提供平均功率110W，峰值包络功率500W，功率增益19dB，漏极效率46%，VDS 电压50 V，漏极静态电流1.3A。本文主要介绍了BLF888主要特性和优势，AB类共源宽带放大器电路和元件列表以及PCB布局图和元件布局图。

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

BLF888应用：

Communication transmitter applications in the UHF band

Industrial applications in the UHF band


图1。BLF888 AB类共源宽带放大器电路

AB类共源宽带放大器元件列表：




图2。AB类共源宽带放大器PCB布局图

图3。AB类共源宽带放大器元件布局图