Keithley 2651A Reference Manual page 34

Section 2: General operation
Model 2651A source-measure capabilities
Range
100 mV
1 V
10 V
20 V
40 V
1 µA
10 µA
100 µA
1 mA
10 mA
100 mA
1 A
5 A
10 A
20 A
50 A
Maximum power = 202 W
Compliance limit
When sourcing voltage, the Model 2651A can be set to limit current or power. Conversely, when
sourcing current, the Model 2651A can be set to limit voltage or power. The Model 2651A output will
not exceed the compliance limit. The maximum compliance limit is the same as the maximum values
listed in the following table. Note that the compliance value will limit in either polarity regardless of the
polarity of the source or limit value. The accuracy of the limit opposite in polarity from the source is
diminished unless the instrument is in sink mode. The maximum compliance limits are based on
source range. For more information, see the
The instrument's compliance limit operation changes dependent on the source mode (current or
voltage), load, and the configured limits (current, voltage, and power). It is important to distinguish
both the current and voltage limits from the power limit. As the names imply, the current limit restricts
the current for sourced voltage, and the voltage limit restricts the voltage for a sourced current. The
power limit, however, restricts power by lowering the present compliance limit in effect (voltage or
current) as needed to restrict the SMU from exceeding the specified power limit. For additional details
on using limits, including load considerations when specifying both a current (or a voltage) limit and a
power limit, see the
The only exception to the compliance limit not being exceeded is the VLIMIT when operating as an
ISOURCE. To avoid excessive (and potentially destructive) currents from flowing, the VLIMIT will
source or sink up to 160 mA for ISOURCE ranges on or below 100 mA. For the ranges 1 A and 5 A,
the maximum current is 5.4 A. For ranges 10 A and above, the maximum current allowed is the
current source setting.
2-12
Model 2651A High Power System SourceMeter® Instrument Reference Manual
Source Measure
± 101 mV ± 102 mV
± 1.01 V ± 1.02 V
± 10.1 V ± 10.2 V
± 20.2 V ± 20.4 V
± 40.4 V ± 40.8 V
± 1.01 µA ± 1.02 µA
± 10.1 µA ± 10.2 µA
± 101 µA ± 102 µA
± 1.01 mA ± 1.02 mA
± 10.1 mA ± 10.2 mA
± 101 mA ± 102 mA
± 1.01 A ± 1.02 A
± 5.05 A ± 5.1 A
± 10.1 A ± 10.2 A
± 20.2 A ± 20.4 A
± 50.5 A ± 51 A
Operating boundaries
Compliance principles
(on page 4-5) topic.
NOTE
(on page 4-2) topic.
2651A-901-01 Rev. A / March 2011