Bulk-driven DC level shifter

A new CMOS DC level shifter that can be programmed at a level less than the threshold voltage of a MOSFET is proposed. This design technique utilizes a bulk- driven MOSFET, which is biased with a constant reverse voltage, to shift the input. Furthermore since the proposed block is in a class-AB super source follower form, it is power- efficient. This paper presents the design and the simulation of the proposed block and also its application in a simple current mirror using a 0.35μm CMOS process, which indicates leading to the reduction of the voltage headroom consumption of the input device but without introducing DC offset current, while the additional distortion remain negligible until 1MHz operation. The additional static current consumption is as small as 5μA.