Little Class D question

[The Dragon]

Dear members of this forum 🙂

I'm not studying electronics, but for some project at school they require us to make everything by us selfs.

I have this little scheme that describes a simple class D

my question is I can't simulate this thing because multisim does not have components like the BAT 54 diode, opamp AD8651 and the AC type shmitt-trigger (74AC14)

I wanted to simulate the effects of using different IC's to determine the fastest one or an equivalent IC if they don't have the one I need in the shop.

so my question finally is can someone simulate this for me or are there any programs for free that does have the required components?


btw: if anyone needs the scheme, just mail me 🙂

thanks in advance

 

[fumac]

u can use swcad III from LT
is great for class-d and other switch things
www.linear.com/designtools/software/switchercad.jsp

rg
fumac

 

[The Dragon]

it is a great program idd, but from what I have I'll need to modificate my scheme, because it does not have 74x IC's

kinda sucks, I was going to make it today and hope it goes well 🙂

 

[Genomerics]

There is an LTspice user group on Yahoo.... It's run by Helmut Sennewald who is a really helpful bloke.

http://tech.groups.yahoo.com/group/LTspice/

You have to join

Once you have then in the files section under lib.....

http://tech.groups.yahoo.com/group/LTspice/files/ Lib/

You get lots of nice stuff including models for 4000 series and 74 series logic.

http://tech.groups.yahoo.com/group/LTspice/files/ Lib/Digital 74HCTxxx/

I'll probably get this wrong but...... You put the .lib file into the LTspice library directory..... under sub

C:\Program Files\LTC\SwCADIII\lib\sub

Then you extract the symbol files into a directory you create with a suitable name under sym

C:\Program Files\LTC\SwCADIII\lib\sym

LTspice will pick up on that and they should appear on the part you place components with.

To use the bits you have to place a spice directive on you schematic, for example.

.include C:\Program Files\LTC\SwCADIII\lib\sub\CD4000.lib

If that doesn't work ask on the forum.......

Have fun

DNA

 

[The Dragon]

Thank you very much 🙂