Hi, I'm planning to use a RF6886 linear power amplifier for a project. It should operate around 144MHz and the problem is that the data sheet does not provide any data about these range of frequencies. It provides data for the 433MHz-470MHz and 865MHz-955MHz ranges only. I don't know if I'm missing something but I cant figure out how to choose the adequate components for the input and output pins, I mean, to match the impedances with the rest of the "world". I assume that the inductor-capacitor T connected at the input is a matching network. Is there any way to find out the input impedance of the chip at 144MHz using the data sheet or should I get it experimentally?

Here is the data sheet http://www.rfmd.com/CS/Documents/RF6886DS.pdf

Thanks in advance.

 

Hello,

In the datasheet is given that it can be used for 100 to 1000 Mhz.

Product Description

The RF6886 is a linear, high power, high efficiency amplifier designed to use as a
final stage/driver in linear or saturated transmit applications. The device is manu-
factured on an advanced InGaP HBT process and is provided in a 24-pin leadless
chip carrier with backside ground. External matching allows for use in standard
bands from 100MHz to 1000MHz.

With the correct input and output matching it can be used on 144 Mhz.

Bertus

 

The problem is that the datasheet doesn't provide the input impedance at all frequencies. I should know it at 144MHz in order to pick the components of the matching network.

 

For $100,000 or so you could get a VNA and measure it. You might find one a bit cheaper on eBay. g\Good Luck.

 

For $100,000 or so you could get a VNA and measure it. You might find one a bit cheaper on eBay. g\Good Luck.

Perhaps you could make an educated guess and adjust accordingly? Or are you working with high enough power that you might fry something if the impedance isn't matched just right?