A Compact Wide-swing Self-biased Cascode Current Mirror for Wide Dynamic-range Applications

The cascode current mirror is the most widely used block in analog circuit design, and wide voltage swing operation is essential for low-supply voltage applications. In wide dynamic-range applications, such as current sensing in DC-DC converters, the current mirror must maintain high accuracy across a wide range of reference currents while enabling wide voltage swing operation at the maximum reference current. In this paper, a wide-swing self-biased cascode current mirror for wide dynamic-range applications is described. Unlike conventional structures, the proposed design is biased by a non-isolated active device without using an extra current path or an isolated active device. The proposed current mirror demonstrates higher accuracy for a wide-range of reference currents compared to prior wide-swing cascode current mirror designs and offers a more compact design.