simple squarewave generator

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Mdkanz

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I'm not sure if this is possible to make but i need a square wave generator that is fairly simple.
It needs to be about nine volts in and out at about 50-150hz and has to have two outputs that are 90 deg out of phase from each other. I was looking at the lm555 timer but don't know how i could get two outputs.
 
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Once set will the frequency be fixed or do you want it to be adjustable in the final circuit between 50 - 150 hz? How accurate does the 90 degree phase difference have to be? Can you use a micro-controller?
 
How about a simple astable as a clock running at four times your desired rate clocking two D flip flops wired as a four-state Johnson counter. The outputs of the the two flop are in quadrature.
 
I think the diodes on the schematic I previously linked to have been connected incorrectly. It looks like they're supposed to act as a limiter so they should be in reverse parallel.

Here's another digital idea:

You could use a two-bit counter and oscillator.

The XOR of both outputs and output B is quadrature.

This could easily be implemented using a CD4060 and an XOR gate.
 
try the attached circuit, you need 8x (50-150Hz) to feed it the output would be 50-150Hz two clocks with 90 deg phase shift.
 

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That's a little complicated isn't it?

I've drawn up my idea which is much simpler.

The XOR gate can be made from a quad NAND, if you don't have any XOR gate ICs.

**broken link removed**
 

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  • 4060 Quadrature..PNG
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That's a little complicated isn't it?

I've drawn up my idea which is much simpler.

The XOR gate can be made from a quad NAND, if you don't have any XOR gate ICs.

**broken link removed**

you are correct with the truth table, and if you have A&B signals you can get as required. also i made a mistake on my diagram that its 45 phase shift not 90, small change on pin connection would offer 90.

you have to connect the reset of 4060.
 
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