The 225 is a Current Source from Keithley. A current source is a type of electronic test equipment in circuit form that can deliver or absorb electrical current that’s independent of the voltage across its terminals. There are two types of current sources: dependent and independent. A dependent current source delivers an electric current that is proportional to another voltage in the circuit. An independent current source delivers a constant current.
3 digit readout
100 V max
Accuracy of ± 0.5% of reading, ± 0.05% of full range
The 225 True Bipolar Current Source provides outputs from 10E-07 A to 10E-01 ADC in seven decade ranges.