Function Generator with Burst

Thread Starter

danadak

Joined Mar 10, 2018
4,057
Just fooling around here is an example to do burst wave forms, of any kind.

Using WaveDAC which can do arbitrary waveforms shown is a burst of 5 sine cycles.
There is flexibility in freq, period, amplitude, phase, # cycles, delay between cycles,
continuous or one shot mode.....WaveDAC can be set for traditional, sine, pulse, saw,
tri, or whatever your custom requirements are.

This was implemented on just one channel, could be done up to 4 channels I think with the
DDS clocking front ends. I would have to try latter to see if there is enough resources.

Onechip solution. Note output is buffered by onchip opamp, but that cannot drive 50 ohms,
you would have to add external driver for that.

Freq range of DDS to ~ 1 Mhz, WaveDAC 100 Khz with some harmonics present, 20 Khz
stuff 40 db down or more.

Same approach can be done to do FSK links, same basic approach, but a lot less onchip
resources needed..

upload_2019-4-5_16-46-6.png

upload_2019-4-5_16-46-43.png


I have always had a fascination with f() generators. First design done with a SCAMP running Tiny Basic driving a DAC
back in mid 1970's. Fun stuff. And a lot easier to do these days with the tools and chips we have access to.



Regards, Dana.
 

Thread Starter

danadak

Joined Mar 10, 2018
4,057
Can't any modern function generator do that?
For sure yes, arbitrary f() generator do a lot more than what I show. My
purpose was just showing some capabilities of a mixed signal chip.

Where this part would trump an arbitrary f() generator is ability to do some
very complex sequences and triggering. For example trigger a burst based
on a temperature and light level and count quantity and COM stream and
......basically broad variety of triggering conditions. Or burst a waveshape
whose shape is a f() of some parameter(s), digital; and or analog.

And cost, this is one chip (not including external sensors or external buffering
or display...).

The project is just looking at parts capabilities and what it takes to design.


Regards, Dana.
 
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