Source ±DC current from 0.1pA to 105mA. Voltage compliance limit from 0.1V to 105V in 10mV steps. 11W, four-quadrant sink or source operation (duty cycle limitation for high power sink). Analog filter to slow down output response. Triax cable guarding to optimize output response speed and reduce leak- age currents in high impedance test circuits. Banana jack guard output for voltage measurements. Sweep functions: linear staircase, logarithmic staircase, and custom. Waveform functions (6221 only): Sine, square, ramp, and arbitrary function generator. Five user-saved setups. Delta testing when used with the Keithley Model 2182 or 2182A: • Delta – Uses a square wave output and a 3-point measurement algo- rithm to cancel the effects of thermal EMFs. • Pulse Delta (6221 and 2182A only) – Provides a pulse output and a 3-point (or 2-point) measurement algorithm for testing of temperature sensitive Device Under Test (DUT). • Differential Conductance – Uses a differential current output and a 3-point moving average algorithm to perform differential measure- ments. • Buffer storage and recall for up to 65,536 delta readings • Averaging filtering for delta readings Supported remote interfaces: Model 6220: GPIB and RS-232. Model 6221: GPIB, RS-232, and Ethernet. KI-220 language – DDC commands to emulate Model 220 operation.