A 93.7% peak efficiency DC-DC buck converter with all-pass network based passive level shifter in 55 nm CMOS

This paper proposes a DC-DC buck converter with all-pass network based passive level shifter in 55nm standard CMOS process, for battery powered portable applications. In order to handle high battery voltages in this advanced standard CMOS process, a passive level shifter based on all-pass network is applied for gate oxide protection. Drain extension is proposed to obtain high breakdown voltage of active region. The proposed buck converter with the passive level shifter works in DCM operation as its load current varies from 0.1–10mA. The buck converter achieves a peak efficiency of 93.7% and 83.8% at 10mA load current, with a supply voltage of 1.8V and 3.7V, respectively.