HF power amplifier using low cost MOSFET

[bobytronic]

hf power amplifier

Hi,

I would like to design an HF power amplifier but all the schematics i have found are not in the desired bandwith !!

SPecifications of the amplifier:

Input signal : 0 to 12V between 800Khz and 5Mhz
OUtput signal: 0 to 12V but 60W !!!

I would like tu use a PUSH PULL configuration whith low cost MOSFET (like IRF...). because the RF power mosfet like MRFxxx and ARFxxx are very expensive (30 $ unit) !!!

Could you help me please for this particular design ???

 

[twinsen]

mosfet hf amplifier

I seem to remember seeing a design for something like this using IRF hexfets....

Search for ham hf amplifier irf510 on google...

 

[bobytronic]

irf510 amplifier

Thanks for this link !
**broken link removed**

SOmebody knows how can i simulate this amplifier with ORCAD ?

 

[goodboy_pl]

irf510 rf amplifier

for mhz range u can increase efficiency by using "Low Charge" mosfets like IRF740LC by International Rectifier.
they have LC suffix in their part number.

for rf simulation with LC tanks it is better to use harmonic ballance simulation rather than transient; it is fast and accurate.

u can simulate your ckt with Microwave Office, Serenade or APLAC or ....

BEST!

 

[bobytronic]

irf510 hf amplifier

ok thanks , i try to use MicroWave Office.

I have found an other design of power mosfet amplifier , but the Bandpass is about 100Khz !! Somebody knows which component can limit this BP in this structure ??
(AOP has 100Mhz bandwith) but it doesn't work over 500Khz even without R11 and C5

 

[bobytronic]

hf mosfet amplifier

link for this amplifier :

**broken link removed**