# Frequency amplifier Circuits

Discussion in 'General Electronics Chat' started by king40, Dec 2, 2014.

1. ### king40 Thread Starter Member

Jul 17, 2013
75
0
HI Engineers , Friends
I need some suggest
what is the best:
Powerfully frequency amplifier circuit
for max voltage 18 V ?
Thanks

2. ### GopherT AAC Fanatic!

Nov 23, 2012
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I think there is some confusion with your concept of frequency and amplification.
Frequency can be multiplied to make a higher frequency (but not "powerfully")
- in a mixing process with another signal
- in a frequency doubling type circuit

A signal can be amplified
- current gain
- voltage gain
- combination of both

Please tell us what you are trying to do.

Nov 23, 2012
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4. ### king40 Thread Starter Member

Jul 17, 2013
75
0
Thanks
You Right
"
A signal can be amplified
- current gain
- voltage gain
- combination of both
"
my means exactly both of them
amplifier Current and Voltage of frequency

5. ### GopherT AAC Fanatic!

Nov 23, 2012
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Ok, then you need to use the word, "signal" instead of "frequency"

Now, we need to know more about the signal you have...
-What is the shape of the wave form?
-what is the frequency
-What are you using to make the wave form (Microcontroller, radio receiver, oscillator from linear or digital ICs, ...)
-What is the voltage

Now, what voltage and load do you need to drive with your amplified waveform?
Tell us what you want to do.

6. ### king40 Thread Starter Member

Jul 17, 2013
75
0
-shape is square
- make with Microcontroller
- Output from Microcontroller so voltage is 5v ( must be amplifie)
- working on circuit
Voltage is 5v because my Generator is Micro So i want to amplifier signal
and max voltage is 18V

7. ### GopherT AAC Fanatic!

Nov 23, 2012
6,314
4,033
So, a simple logic level N-mosfet switch will work.

SOURCE pin to ground

DRAIN Pin to your load (39 ohm resistor, for example) to allow 500 mA to go through at 18 volt supply

Then connect your Microcontroller pin to a 10 ohm resistor and your 10 ohm resistor to the GATE pin on your Mosfet

Connect a 100k resistor from the GATE pin to ground.
Finally, make sure to connect the ground wires powering your micro to the ground wire powering your mosfet.

Make sure you use a "logic level" mosfet. That is, one that turns on completely when the gate voltage is at 5 volts (or even less).

Last edited: Dec 2, 2014
8. ### king40 Thread Starter Member

Jul 17, 2013
75
0
Thanks
this is Powerfully?
any n-mosfet can do this?

Apr 9, 2011
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10. ### king40 Thread Starter Member

Jul 17, 2013
75
0
You Can Give Me a Circuit For Example ?

11. ### MrChips Moderator

Oct 2, 2009
12,636
3,454
Or a simple NPN BJT will do.

12. ### wayneh Expert

Sep 9, 2010
12,388
3,245
Follow the words in #7 carefully. He has given you the details you need. Search for "MOSFET switch" for more general information.

Oh wait, Gopher made a booboo. He meant "gate" where he wrote "drain" in lines 5 and 6.

Last edited: Dec 2, 2014
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13. ### WBahn Moderator

Mar 31, 2012
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What do you mean by "Powerfully"?

That is like saying that you want a light that is bright and someone gives you a 300W halogen but you had in mind something that could start a piece of paper on fire from ten feet away in under a second. Or, the reverse, someone gives you a light that starts paper on fire in a flash but you just wanted to better illuminate your living room.

You need to determine what you need, in concrete terms, and then communicate it to us.

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14. ### GopherT AAC Fanatic!

Nov 23, 2012
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FIXED - I Hope!