Tektronix KEITHLEY SourceMeter 2606B Reference Manual page 222

Model 2606B System SourceMeter® Instrument Reference Manual
Voltage source operation in power compliance
The figure below shows what happens if a power limit of 60 mW is applied. As the instrument
attempts to output the programmed source value of 10 V, the power compliance limit line is reached,
placing the 2606B in power compliance. The 2606B enforces the power compliance limit by setting
the current compliance limit line to the new power limited current compliance limit line setting, which
in this case is 8.66 mA. In compliance, the 2606B cannot source its programmed voltage (10 V). For
the 800 Ω DUT, the 2606B only outputs 6.928 V (at the 60 mW limit). In this example, current never
exceeds the programmed compliance of 10 mA, or the programmed power compliance of 60 mW,
under any load.
Voltage source sweep operation in current and power compliance
The following figure shows a voltage sweep on a resistive load of 800 Ω. For this example, the 2606B
is programmed to sweep voltage to 10 V, limit current (6 mA) and limit power (50 mW). When
sweeping, the actual source output varies according to the programmed source value until the current
limit is reached. As the figure shows, the output sources the programmed value until placed in current
compliance at the 6 mA limit. The sweep then continues. Programmed current source values increase
along the green sweep points line, but the output remains at the value it was at 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 (50 mW). At this point, the current and voltage start
to decrease, lowering the current and voltage values along the DUT load line. When the last point is
swept (10 V), the actual output is 10 V (at 5 mA).
2606B-901-01 Rev. C November 2021
Figure 90: Voltage source operation in power compliance
Section 8: Theory of operation
8-7