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Is it possible i use this LDMOS for wide BW?

Dummyeng

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dick_freebird

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LDMOS are meant for switching and so are
probably intended for Class C, Class E type
PAs which tend to have tuned output match
transforming the pulsed waveform into a
single (passed) frequency out the back.

That (tuned load) fights against wide and flat
amplifier bandwidth / response.

LDMOS are good for high blocking and low
on resistance, but not at the same time -
power dissipation within the core device
is highly concentrated / uneven and the
same power handling, steady state, per
die area may be less than a device with more
uniform and less interconnect-adjacent
(like vertical) heat-throw by construction.

What you "can get" in simulation, and what
the hardware can survive, are separated by a
gap in knowledge and modeling and post
analysis (like temp rise at the drain contact
and the metallization above, vs junction temp
dependent lifetime, from electrical / thermal
TCAD or direct measurement at microscopic
scale (such as an IR camera microscope)).
 

BigBoss

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In order to widen the Amplifier's Bandwidth, you should use "Wideband Coupler/Balun Components".
In additional to this, Optimum Load Impedances that are given for single frequency, they are a little bit different so the task will be a bit complicated but it's possible to obtain good performance from this transistor.
However, you should able to reach some expensive state of art Measurement Equipment such as Load Pull/Source Pull Automated Tuner.Because even-tough the Optimum Impedances are given but they are Typical Values and they change by different manufacturing dates and process lots.
Because your frequency is pretty high and Output Power is too high.You cannot design such Power Amplifier without Measurement and each transistor has to be measured before starting to design.You're gonna later on select a Compromise for both Bandwidth ends (900 and 1300MHz) in terms of Power Gain,max. Delivered Power and Efficiency.
In my first sight, this transistor looks adequate and you can go with it but as I said before you should examine your design very carefully by researching the RF Component market to find appropriate components and surely Design Techniques in Technical Literature.
 

FvM

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Polyfet has published a large number of design applications for LDMOS and VDMOS wideband amplifiers using transmission line transformers for impedance matching. www.polyfet.com/tbpltf.htm
 

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