The transistors string, which consists of K identical PMOS
transistors, samples the supply voltage. The drain-to-source
voltage (VDS) of each transistor is one over K of VDD. Each
PMOS transistor lays with bulk tied to the source to make sure
that the threshold voltage is identical. The PMOS transistor
MpDM shares the identical figure dimension of MpDl but with
different figure numbers. As a result, MpDM duplicates the
current through MpDl with a multiplier ofN, and thus the Idle is
presented as