Kerry Wong did a teardown of an Agilent 66312A dynamic measurement DC source:
Typically, a lab power supply can only operate within a single quadrant. Take a positive voltage power supply for example, it can only output or source current. If any attempt is made trying to sink current into the power supply by connecting a voltage source with a higher voltage than the output voltage of the power supply, the power supply would lose regulation since it cannot sink any current and thus is unable to bring down and regulate the voltage at its output terminals.
The Agilent 66312A dynamic measurement DC source however is a two-quadrant power supply, it not only can source up to 2A of current between 0 and 20V, but also can sink up to 1.2A or 60% of its rated output current as well. Although lacking some key functionality of a source measure unit (SMU), Agilent 66312A can nevertheless be used in similar situations where both current sourcing and sinking capabilities are needed.
More details on Kerry Wong’s blog.
Check out the video after the break.