Section 4: Theory of operation
2606B System SourceMeter® Instrument Reference Manual
4-6
2606B-901-01 Rev. B / May 2018
Voltage sorce operation in current compliance
In the following figure, the resistance of the load is decreased to 800
Ω. The DUT load line for 800 Ω
intersects the current compliance limit line, placing the 2606B in compliance. When it is in
compliance, the 2606B cannot source its programmed voltage (10 V). For the 800
Ω DUT, the 2606B
only outputs 8 V (at the 10 mA limit).
Notice that as resistance decreases, the slope of the DUT load line increases. At zero resistance
(shorted output), the 2606B sources virtually 0 V at 10 mA. Conversely, as resistance increases, the
slope of the DUT load line decreases. As resistance approaches infinity (open output), the 2606B
sources virtually 10 V at 0 mA.
Figure 81: Voltage source operation in current compliance
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.