Apparatus and method for providing a supply voltage to a device under test using a capacitor

An apparatus for testing, the apparatus comprising:

• a circuit operable to provide a supply voltage to a device under test, the circuit comprising:
• a controlled source configured to provide a voltage at an output based on one or more control signals;
• a switchable resistor coupled between the output of the controlled source and a device under test, the switchable resistor having a first resistance in a first switch state and a second resistance in a second switch state, wherein the second resistance is smaller than the first resistance;
• a regulator configured to provide a first control signal of the one or more control signals to the controlled source, wherein the regulator is further configured to regulate a voltage provided to the device under test based on an information about a desired voltage;
• and
• a capacitor coupled in parallel with the switchable resistor during switching of the switchable resistor and configured to slow a voltage change across the switchable resistor, wherein the voltage change is responsive to changing a switch state of the switchable resistor,
• wherein the circuit is configured to change a switch state of the switchable resistor while a voltage is provided to the device under test via the switchable resistor.