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The blocks here make use of LTspice's builtin mathematical functions, plus a few others. The appearance of the symbols was made with the thought of uniformity in mind and a more stream-lined approach, which makes possible changing the function of the symbol on the fly. Placing the Math1 symbol with its default abs value means the symbol will perform the abs() function. Changind the functions can be done by either renaming or by right-clicking the symbol and selecting the desired entry from the drop-down menu. For example switching from sin() to cos() means renaming sin to cos, or having b-a instead of a-b means adding a + after -, as can be seen in the images below:

Renaming SIN to COS B-A instead of A-B

This also means that the schematic will look uniform, all the mathematical functions will look the same so they will be easily recognized, while, at the same time, their functions will be clearly spelled out.

The library files are divided into three: mathfunc.sub, holding the constant value block and the 5-input summer, mathfunc1.sub, holding the one-variable functions (e.g. sin(x), x being the input), and mathfunc2.sub, holding the two-variable functions (e.g. atan2(a,b), a and b being the inputs). Sometimes, in addition to the usual input(s) as variable(s), there are some other parameters that can be defined, e.g. the atan2 block has the additional parameters a (the signum for the input a), b (the signum for the input b) and dc (the DC offset). All the blocks have floating input and 1Ω output resistance, unless otherwise noted. The list of blocks inside [Math] is as follows:

Const mathfunc.sub Constant value, though it's a B-source inside so it can have functions, too.
Math1 mathfunc1.sub One-variable input functions. Unlike Math2, the names are the same as their LTspice counterparts. Some of them have additional parameters, this is the list:
function additional parameters
1/x y sets the minimum number to avoid division by zero, the output will be maximum of 1/y
abs
acos phi sets the phase
acosh
asin phi sets the phase
asinh
atan phi sets the phase
atanh
ceil
cos phi sets the phase
cosh
exp
floor
int
ln
log
log10
mod1 V(in) is divided to y, mod(V(in),y)
pow y is the exponent as defined by LTspice, pow(V(in),y)
pwr y is the exponent as defined by LTspice, pwr(V(in),y)
pwrs y is the exponent as defined by LTspice, pwrs(V(in),y)
quant y is the number the quantizing is done with, int(V(in)*y)/y
round
sgn y sets the offset, sgn(V(in)+y)
sin phi sets the phase
sinh
sqrt
tan phi sets the phase
tanh
u y sets the offset, u(V(in)+y)
uramp y sets the offset, uramp(V(in)+y)
Math2 mathfunc2.sub Two-variables input functions. This is the list:
function name additional parameters
a+b +
a-b -
b-a -+
a*b *
a/b / min sets the minimum number to avoid division by zero, abs(V(b))/min
b/a /* min sets the minimum number to avoid division by zero, abs(V(a))/min
a==b ~~
(LTspice allows "==" as naming but doing so won't have any effect)
a<>b <>
atan2(a,b) atan2 a sets the signum of V(a), b sets the signum of V(b) and dc sets the DC offset added to the total:
atan2( sgn(a)*V(a), sgn(b)*V(b) ) + dc
hypot(a,b) hypot
max(a,b) max
min(a,b) min
mod(a,b) mod
Math2r mathfunc2.sub The same functions as Math2 only with a round symbol and 90o inputs.
Math2rT mathfunc2.sub The same functions as Math2 only with a round symbol and opposite inputs.
Math5 mathfunc5.sub 5-input sum/difference, any combination possible, except nulls (this may replace Math5r in the future):
+++++
-++++
+-+++
++-++
+++-+
++++-
--+++
-+-++
-++-+
-+++-
+--++
+-+-+
+-++-
++--+
++-+-
+++--
---++
--+-+
--++-
-+--+
-+-+-
-++--
+---+
+--+-
+-+--
++---
----+
---+-
--+--
-+---
+----
-----
Math5r mathfunc.sub 5-input summer.

All the models are archived inside one file and are available in two flavours:

Zip archive: Math.zip (7917 B) 7z archive: Math.7z (4575 B)






































































































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