Difference between revisions of "Adding a permanent component to LTspice"

From LTwiki-Wiki for LTspice
(Adding LM339 as a Comparator)
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An Example using LM339 [http://alternateenergies.com/LTwiki/files/LM339_test.asc LM339_test.asc]
 
An Example using LM339 [http://alternateenergies.com/LTwiki/files/LM339_test.asc LM339_test.asc]
 +
[http://alternateenergies.com/LTwiki/files/LM339_LTspice.png A screenshot of the LM339 test file]

Revision as of 19:18, 9 August 2009

Adding LM339 as a Comparator

This technique allows you to add a frequently used part to the menu of LTspice. In this way you don't have to use include statements, etc. These parts should not be overwritten during an LTspice update.

1) Start with an existing .asy file if possible. Here we can use LT1017.asy:


Version 4
SymbolType CELL
LINE Normal -32 -32 32 0
LINE Normal -32 32 32 0
LINE Normal -32 -32 -32 32
LINE Normal -28 -16 -20 -16
LINE Normal -28 16 -20 16
LINE Normal -24 20 -24 12
LINE Normal 0 -32 0 -16
LINE Normal 0 32 0 16
LINE Normal 4 -20 12 -20
LINE Normal 8 -24 8 -16
LINE Normal 4 20 12 20
WINDOW 0 16 -32 Left 0
WINDOW 3 16 32 Left 0
SYMATTR Value LT1017
SYMATTR Prefix X
SYMATTR SpiceModel LTC1.lib
SYMATTR Value2 LT1017
SYMATTR Description µPower Dual Comparator(1 of 2)
PIN -32 16 NONE 0
PINATTR PinName In+
PINATTR SpiceOrder 1
PIN -32 -16 NONE 0
PINATTR PinName In-
PINATTR SpiceOrder 2
PIN 0 -32 NONE 0
PINATTR PinName V+
PINATTR SpiceOrder 3
PIN 0 32 NONE 0
PINATTR PinName V-
PINATTR SpiceOrder 4
PIN 32 0 NONE 0
PINATTR PinName OUT
PINATTR SpiceOrder 5

2) Edit the lines above as shown:

WAS:

SYMATTR Value LT1017
SYMATTR Prefix X
SYMATTR SpiceModel LTC1.lib
SYMATTR Value2 LT1017
SYMATTR Description µPower Dual Comparator(1 of 2)

NOW:

SYMATTR Value LM339
SYMATTR Prefix X
SYMATTR SpiceModel LM339.sub
SYMATTR Value2 LM339
SYMATTR Description Quad Single Supply 3V/5V Comparator LM339

3) Save this file as LM339.asy under \lib\sym\Comparators LM339.asy

4) Put LM339.sub file, put in \lib\sub

5) When LTspice opens again, LM339 should be available as a component under 'Comparators'.

Note: Additionally look at LM339_DIP14.asy You may add this as well, if you want all four comparators.

An Example using LM339 LM339_test.asc A screenshot of the LM339 test file