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Oscillator

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You still really haven't provided enough information.

Do you want to switch the low/high side?

Do you need a pulse with at +/-12V?

Or do you need to switch an h-bridge?

I want the Oscillator to reaches to positive MAX then to zero and then to Negative MIN.
 
You mean like this?

Same with the sine wave?

How much current do you need?

The trouble is there will be some voltage loss, especially with the sinewave so if you need 12V peak then it might be a good idea to bump up the supply voltage to 15V.
 

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Here's a function generator I was talking about earlier. It gives a sine, triangle and square wave outputs and only needs one resistor to alter the frequency.

You obviously, need to select components which will work at the desired frequency and have another amplifier on the sinewave output to give 12V peak to peak. You could get the whole thing done with one quad op-amp IC.

EDIT:
Another amplifier isn't required except for the square wave, if you're worried about loading. The output voltage can be increased to nearly 12V by increasing the value of R13 to 82k.

R6 to R12 need to have a tolerance of at 1% maximum.
 

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Last edited:
I've tried simulating it and it gives pules.

Simulators can be wrong of course, what values did you use? I guessed.

For some reason I couldn't attach the .asc file so here it is:
Code:
Version 4
SHEET 1 1060 680
WIRE 528 -336 496 -336
WIRE 672 -336 608 -336
WIRE 672 -304 672 -336
WIRE 688 -240 672 -240
WIRE 256 -192 256 -208
WIRE 368 -192 256 -192
WIRE 544 -192 544 -240
WIRE 256 -160 256 -192
WIRE 368 -144 368 -192
WIRE 544 -96 544 -128
WIRE 592 -80 592 -240
WIRE 256 -64 256 -80
WIRE 368 -32 368 -64
WIRE 464 -32 464 -240
WIRE 464 -32 368 -32
WIRE 528 -32 464 -32
WIRE 368 0 368 -32
WIRE 592 32 592 16
WIRE 368 112 368 80
FLAG 256 -64 0
FLAG 256 -208 +V
FLAG 688 -240 +V
FLAG 544 -96 0
FLAG 592 32 0
FLAG 368 112 0
FLAG 672 -304 0
SYMBOL ind2 512 -352 M90
WINDOW 0 4 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName L1
SYMATTR Value {Ls}
SYMATTR Type ind
SYMATTR SpiceLine Rser=1
SYMBOL ind2 560 -224 M270
WINDOW 0 32 56 VTop 0
WINDOW 3 4 56 VBottom 0
SYMATTR InstName L2
SYMATTR Value {Lp}
SYMATTR Type ind
SYMATTR SpiceLine Rser=1
SYMBOL ind2 576 -224 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 4 56 VBottom 0
SYMATTR InstName L3
SYMATTR Value {Lp}
SYMATTR Type ind
SYMATTR SpiceLine Rser=1
SYMBOL voltage 256 -176 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 12V
SYMBOL npn 528 -80 R0
SYMATTR InstName Q1
SYMATTR Value 2N3055
SYMBOL Misc\\EuropeanResistor 352 -160 R0
SYMATTR InstName R1
SYMATTR Value 470R
SYMBOL Misc\\EuropeanResistor 352 -16 R0
SYMATTR InstName R2
SYMATTR Value 470R
SYMBOL Misc\\EuropeanPolcap 528 -192 R0
SYMATTR InstName C2
SYMATTR Value 1µ
TEXT 720 -136 Left 0 !.tran 5m
TEXT 720 -104 Left 0 !.param N=10
TEXT 728 -40 Left 0 !k1 L1 L2 L3 1
TEXT 720 -72 Left 0 !.param Lp=470u Ls=470u

Well I know this is off topic but he won't really give us the info we need. So let's discuss this "Armstrong" oscillator. It is just an normal sine-wave oscillator. Of course you could make it clip or saturate but I have never had one do that. It gets it's positive feedback through the "tickler" coil. So this is analog. As the collector current rises, the tickler which is would 180 degrees out of phase is feeding a small portion of the output back into the base. So the diagram I used has a transformer, but the secondary is not needed for it to work. So the oscillator its self really only needs two windings. The main inductor with an out of phase tickler coil which is just a few turns over the same core.

It's performance is sign wave but it has a hefty output. Therefore it is not very stable. I would never use it for any sort of frequency control, but if you need a good high gain oscillator source it will do the job. They make nice DC-DC converters. In fact that's what the secondary was for. I stepped up the voltage to drive a fluorescent lamp.
 
Your schematic didn't give any component values; could you please provide them?
 
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