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AnsweredHot!Can i make a very fast squarewave with peripherals ?

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Jan Audio
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Re: Can i make a very fast squarewave with peripherals ? 2020/11/23 08:45:36 (permalink)
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The nice thing is i can use 100 and it cost no power.
In the best MCU it cost you at least 1 amp.
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dan1138
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Re: Can i make a very fast squarewave with peripherals ? 2020/11/23 11:23:55 (permalink)
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Jan Audio
The nice thing is i can use 100 and it cost no power.
In the best MCU it cost you at least 1 amp.

I can see you are committed to old school methods.
Stay in your comfort zone and best of luck.
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Jan Audio
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Re: Can i make a very fast squarewave with peripherals ? 2020/11/24 06:45:11 (permalink)
+1 (1)
Thanks, i just use everything that works.
If i have my PIC32 all set-up i can make a digital delay also, with some SMD soldering on converter sockets.
Now i only have the very noisey DSPIC33FJ128GP802 working, not good for a delay.
Those high-quality audio-DACS and ADCs are only in SMD.
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davea
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Re: Can i make a very fast squarewave with peripherals ? 2020/11/24 11:15:30 (permalink)
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The easy to use SigmaStudio™ software allows the user to graphically configure a custom signal processing flow using blocks such as biquad filters, dynamics processors, level controls, and GPIO interface controls.
simple to use...
have a look
https://www.analog.com/me...a-sheets/ADAU1401A.pdf
https://www.analog.com/en/parametricsearch/11310#/
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OsvaldoH
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Re: Can i make a very fast squarewave with peripherals ? 2020/12/03 10:04:39 (permalink)
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CWG may be usefull. (complementary pwm outputs)
From MN3207 datasheet, please be aware that the two clk inputs have 700pf max.
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Jan Audio
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Re: Can i make a very fast squarewave with peripherals ? 2020/12/03 10:09:28 (permalink)
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I dont add any capacitors on those inputs, it works good without.
Just got my V3205 chips, nice for long delay.
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OsvaldoH
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Re: Can i make a very fast squarewave with peripherals ? 2020/12/03 11:37:38 (permalink)
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from datacheet 3205   -  2800pf for clk input
This is the internal capacitance of the chip.
If you connect directly to PIC output, there are big current spikes , the same as with any big capacitive load.
I suggest a 150  Ohm (or greater)  in serie for limiting the output current
 
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Jan Audio
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Re: Can i make a very fast squarewave with peripherals ? 2020/12/04 06:28:08 (permalink)
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Ok so i dont need to add capacity only a resistor.
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oliverb
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Re: Can i make a very fast squarewave with peripherals ? 2020/12/04 08:09:28 (permalink)
-1 (1)
For a properly old school approach you probably ought to be using a VCO, such as the VCO block of a CD4046/74HC4046 PLL, to create the clock.
 
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OsvaldoH
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Re: Can i make a very fast squarewave with peripherals ? 2020/12/04 10:48:33 (permalink)
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I have attached the 3102 datasheet , that is used in the example circuit from MN3207 datasheet
 
This clk generator has a low current capability and donýneed a serial resistor.
In the acese of pic pins output , they can give a lot of current, but max. allowed is 25mA 
(as I remember at the moment)
So with a capacitive load (more than 50pf?), the current must be limited with a resistor intercalated in series.
220 Ohm with 5V  in Vcc , gives a near 20mA limit
As it is not a DC load, may it be use a smaller resist., but it requires more study.
 
It is necesary to define if you need several diferent freq. or you will seep freq. in a continuous mode.
Respect of two complementary outputs, any HCMos inverter can do this with a very little delay
 
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