According to the definition of the uramp function, and I quote, ""uramp" is the integral of the unit step. The unit step is one if its argument is greater than zero and zero if its argument is less than zero. The ramp function (uramp) is 0 for argument values less than zero and equal to the argument for argument values greater than zero.

Despite the misleading title, implying an integral, the uramp function returns the value of the argument when it is greater than zero. Thus, in some cases, where the 'test' is to return the value of the test when it is greater than zero, the uramp function can save some typing, and resultant errors. In other words, where an expression is to be logically,

The following circuit illustrates this:

Figure 1
uramp function test circuit

The netlist for the test circuit is:

The resultant output is shown in Figure 2 following:

Figure 2
uramp function test output

Although not clear from the picture, the input at N4 overlaps the output at N2.

I was misled by the 'ramp' part of the uramp name, actually intending to use it for another purpose; however, the intended purpose can be attained in other manners. Notice several other things. Besides being useful for logic expressions, this also functions as an ideal diode with no voltage drop.

It pays to muck around with the library functions!!!!