A current sense circuit that measures current passing through a
multi-transistor switch, each transistor in configured in parallel. The
current sense circuit mirrors the current in the switch through a mirror
current branch that includes a mirror transistor. The current sense
circuit obtains an accurate measure of current through the switch by
applying voltages at the source and/or drain terminals of the mirror
transistor that more closely approximate the average source and drain
terminals of the constituent transistors of the switch. Thus, relatively
accurate switch current measurements may be obtained.