Electronics > Beginners

555 LT Spice issues (trying to produce ~7kHz ~sine wave)

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iMo:
Updated the zip file above. Put all the stuff into the working folder.

jpyeron:
thanks, i know see the changes you made to the lib.
removed LAMBDA=2E-3 from:
.MODEL TLC55X_NMOSD_HV NMOS LEVEL=3 L=10U W=100U KP={KPN} VTO={VTOHN} LAMBDA=2E-3 THETA=1.8E-01
+ CJ={CJN} CJSW={CJSWN} CGSO={CGSON} CGDO={CGDON} RSH= 10 PB=0.65 LD= 70N TOX={TOX}

removed LAMBDA=2E-3 from:
.MODEL TLC55X_PMOSD_HV PMOS LEVEL=3 L=10U W=100U KP={KPP} VTO={-VTOHP} LAMBDA=2E-3 THETA=2.2E-01
+ CJ={CJP} CJSW={CJSWP} CGSO={CGSOP} CGDO={CGDOP} RSH=10 PB=0.65 LD=70N TOX={TOX}

added:
.PARAM VT=BOLTZ*(TEMP+273.15)/ECHARGE
on
.MODEL DZ_18V D( IS={ISz} N={Nz} BV=18.0 IBV=5.0M EG={8*Nz*VT})

iMo:
I have not made the changes. See the author of the changes in one of the .asc files.

Zero999:
It's possible to import the model into the .asc file to avoid multiple files.

The sine wave doesn't look great and it will require a buffer to reduce the output impedance.

MagicSmoker:
Filtering a square wave oscillator to get a sine wave is a bit kludgy, and if you are going to have to buffer the output then you might as well make an op-amp or transistor based oscillator. For example, the Colpitts configuration is a good choice that is easy to design, outputs a nice sine wave, and is fairly stable over time and temperature if NP0 ceramic capacitors are used. A good explanation can be found here:

https://www.electronics-tutorials.ws/oscillator/colpitts.html

Usually the gain element is a single NPN transistor, but an op-amp can be easier to get working; just make sure gain is at least 3 (but don't go too high or you'll get clipping). If you need a precise peak-to-peak voltage level then it is safest to feed the output of the oscillator into a voltage divider then buffer that with an op-amp follower, if necessary.

If you want to avoid using an inductor (which seems to be a common fear among beginners), then there are many other op-amp based oscillators that rely only on RC networks, though most are (somewhat ironically) more difficult to get working and/or have a less pure output (exception: Wein bridge). In any event, there are so many ways to make a decent 10kHz sine wave oscillator there's really no reason to chose filtering a square wave output from a 555 timer. See, for example, this image collection from a duckduckgo search of "op-amp RC oscillator circuits":

https://duckduckgo.com/?q=op-amp+rc+oscillator+circuits&t=ffhp&iar=images&iax=images&ia=images

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