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Best solution for square wave generator

mikus

Jan 4, 2015
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Hello


I need to build signal generator for square wave were i can change amplitude from 0v to 12v (60Hz).
It is necessary for LCD display shutter testing, LCD display have capacitor characteristics

and I need to drive it and measure

maximum (peak) current mA ,
minimum current (leakage or plateau current) μA,
RMS average current over multiple reference drive cycles μA
RMS average power (RMS average of I(t) V(t) product) over multiple reference drive cycles (μW range)


I hope someone can help with good reading material or advice!
I hope for help, and thank you for attention :)
 

Gryd3

Jun 25, 2014
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Give us some more detail.
How precise do you need to 'square' wave to be?
Is there going to be a duty cycle?

Does the frequency you chose need to be exactly 60Hz? Use in Television equipment or power-grid related equipment of any kind usually runs a little slower... like 59.94Hz

Simplest solution I can think of, is getting or building an adjustable voltage DC power supply in which you can connect a low value shunt resistor that you can use to calculate current draw.
Once you have this, you can make a simple timer with a 555 that will drive a transistor or mosfet that will control the output of the power supply.
 

mikus

Jan 4, 2015
3
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Jan 4, 2015
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Hello


I have need for microcontroller controlled bipolar square wave generator +-15v with adjustable voltage.

I am dreaming of a signal generator witch one i can turn on with arduino, but wen i turn it off i have +15 DC voltage

Frequency must be 60hz but voltage would be nice to have adjustable, 5v,7v,12V,15V

I have bipolar supply +- 15v


I will grateful for any help or ideas

Thank you for help already.

upload_2015-2-26_9-15-7.png

(Moderator action: New post moved to this thread -- KrisBlueNZ)
 
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KrisBlueNZ

Sadly passed away in 2015
Nov 28, 2011
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There are a thousand answers to this question. It all depends on what you're trying to achieve. Start by telling us about the whole project, then we will be able to recommend a suitable way to do what you want to do.
 

mikus

Jan 4, 2015
3
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Jan 4, 2015
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There are a thousand answers to this question. It all depends on what you're trying to achieve. Start by telling us about the whole project, then we will be able to recommend a suitable way to do what you want to do.

My project is a peak and leakage current tester for LCD Shutter cell
LCD cell must be connected to 60Hz bipolar voltage +-1% is Ok
Then with shunt resistor I measure current on LCD cell.
I now how to get peak current value, but I have problems with leakage current.
I think I could turn on frequency generator with arduino and measure peak current, then turn off generator and measure leakage current, like 100ms measuring peak, 100ms measuring leak current

upload_2015-2-26_10-17-5.png
 
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