Keithley 2601B Reference Manual page 242

Section 4: Theory of operation Series 2600B System SourceMeter® Instrument Reference Manual
The following figure shows a current sweep on a resistive load of 200 Ω. For this example, the
System SourceMeter instrument is programmed to sweep current to 100 mA, limit voltage (6 V) and
limit power (500 mW). When sweeping, the actual source output will vary according to the
programmed source value until the voltage limit is reached. As the figure shows, the output will
source the programmed value until placed in voltage compliance at the 6 V limit. The sweep will then
continue (programmed I-source values will increase along the green sweep points line), but the
output will remain at the same value as when the instrument went into voltage compliance. This
continues until the programmed source value sweeps to a high enough level that the power limit line
is reached (500 mW). At this point, the voltage and the current will start to decrease, lowering the
current and voltage values along the DUT load line. When the last point is swept (100 mA), the actual
output would be 25 mA (at 5 V).
Figure 99: Series 2600B I-source load considerations while sweeping I
4-16 2600BS-901-01 Rev. B / May 2013