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Electronics => Beginners => Topic started by: igorbog on October 31, 2011, 08:57:50 pm

Title: Choosing Parts with spice characteristic
Post by: igorbog on October 31, 2011, 08:57:50 pm
Hi
I am a newbie and I have a question.
if I want to build for example oscillator based on opamp. How should I choose parts and where I can get their Pspice models.
THanks
Title: Re: Choosing Parts with spice characteristic
Post by: Simon on October 31, 2011, 09:41:16 pm
the manufacturers website will often supply the model, or it may already be in the software you are susing if it is a well known and used part
Title: Re: Choosing Parts with spice characteristic
Post by: w2aew on November 01, 2011, 02:36:36 am
Hi
I am a newbie and I have a question.
if I want to build for example oscillator based on opamp. How should I choose parts and where I can get their Pspice models.
THanks

The choice of which part to use for an application will depend entirely on what your requirements are.  You'll have to ask yourself some questions like:  What power supply voltage (or voltages) are going to be used?  Does the output need to swing to both supply rails or not?  Do the inputs need to be able to go to the supply rails?  How fast does the circuit have to be?  What kind of supply current can I afford for the opamp?  What kind of load is it going to drive?  How noisy can the output be?  What kind of gain do I need (and still have it be stable)?  How much precision is needed? etc.

Without answering at least some of those questions, you can't begin to narrow down a particular opamp.

Title: Re: Choosing Parts with spice characteristic
Post by: igorbog on November 01, 2011, 06:22:32 am
And after I choose the parts Does the company of the parts should give me the spice model?
Title: Re: Choosing Parts with spice characteristic
Post by: Bored@Work on November 01, 2011, 07:48:08 am
And after I choose the parts Does the company of the parts should give me the spice model?

Some do, some don't.

But I recommend you give up your obsession with SPICE. SPICE is an analysis, not a synthesis tool. It will not magically design your circuit. You alone have to do this.