555 works, but not sure if you could get it to 500khz.
This circuit is not being close to being a perfect sawtooth..Can someone help.....
If you want linear from a UJT , 555, ete, you have to charge the cap with a current regulator. Here's one I'm using, J310, I didn't try for 500kHz yet, if I remember, I'll try today, but with a little adjustment you can get a pretty good saw tooth with a fairly sharp bottom tooth.Anything that just charges a capacitor through a resistor (Unijunction, 555) will not produce a linear sawtooth beacause the voltage vs time is an exponential function.
It takes an integrator (opamp), or a current-source charging a capacitor to create a linear voltage vs time function.
There are many circuits out there that just a modicum of searching will uncover.
Anything that just charges a capacitor through a resistor (Unijunction, 555) will not produce a linear sawtooth beacause the voltage vs time is an exponential function.
It takes an integrator (opamp), or a current-source charging a capacitor to create a linear voltage vs time function.
There are many circuits out there that just a modicum of searching will uncover.
If you want linear from a UJT , 555, ete, you have to charge the cap with a current regulator. Here's one I'm using, J310, I didn't try for 500kHz yet, if I remember, I'll try today, but with a little adjustment you can get a pretty good saw tooth with a fairly sharp bottom tooth.
Kinarfi