General form:

.dc srcnam vstart vstop vincr [src2 start2 stop2 incr2]

Examples:

.dc VIN 0.25 5.0 0.25
.dc VDS 0 10 .5 VGS 0 5 1
.dc VCE 0 10 .25 IB 0 10u 1u
.dc RLoad 1k 2k 100
.dc TEMP -15 75 5

The .dc line defines the dc transfer curve source and sweep limits (with capacitors open and inductors shorted). srcnam is the name of an independent voltage or current source, a resistor, or the circuit temperature. vstart, vstop, and vincr are the starting, final, and incrementing values, respectively. The first example causes the value of the voltage source (V_{IN}) to be swept from 0.25 Volts to 5.0 Volts with steps of 0.25 Volt. A second source (src2) may optionally be specified with its own associated sweep parameters. In such a case the first source is swept over its own range for each value of the second source. This option is useful for obtaining semiconductor device output characteristics. See the example on transistor characterization (21.3).