Replica Biased Voltage Controlled Oscillator for Switching Regulators
In this paper we preset a multi-phase Voltage Controlled Oscillator (VCO) that uses a replica biasing circuit to
ensure that the output swing of the VCO is uniformly distributed across a common mode voltage. Since the VCO output swing
is regulated across the common mode voltage, the output phases are uniformly distributed. The output phases of the VCO can
be used for generating multi-phase switching outputs in voltage regulators. The frequency of oscillation can be controlled
using the current source. Proposed scheme was implemented using 0.18m CMOS technology. It can be seen from the
simulation results that the proposed scheme has a wide tuning range of 1MHz-90MHz and can produce 4 uniform phases.
Index Terms - High Frequency Switching Regulators, Muli-Phase Output, Replica Biasing,Vcos.