System and method of equivalent series inductance cancellation

摘要

An equivalent series inductance (ESL) cancel circuit for a regulator for adjusting a feedback voltage by attenuating a magnitude of a square wave ripple voltage developed on an output voltage. The regulator includes an output inductor and an output capacitor, in which the capacitor has an ESL which forms an inductive voltage divider with the output inductor causing the square wave voltage ripple. The ESL cancel circuit may include first and second current sources and a resistor device coupled between the output node and an adjust node which is further coupled to a feedback input of the regulator. The first current source applies a current proportional to the output voltage to the adjust node. The second current source selectively applies a current proportional to the input voltage of the regulator based on a state of the pulse control signal.

主权项

1. An equivalent series inductance cancel circuit for a regulator including an output inductor coupled to an output capacitor at an output node in which the output capacitor has an equivalent series inductance, wherein the regulator transitions a pulse control signal between inactive and active states for controlling conversion of an input voltage to an output voltage developed on the output node, and wherein said equivalent series inductance cancel circuit comprises:
a resistor device for coupling between the output node and an adjust node, wherein said adjust node is further coupled to an output voltage feedback input of the regulator; a first current source that develops a first current proportional to the output voltage of the regulator, wherein said first current is provided to said adjust node; a second current source that develops a second current proportional to the input voltage of the regulator; and a switch, responsive to the pulse control signal, that couples said second current source to said adjust node to sink said second current from said adjust node when said pulse control signal is in the active state, and that disconnects said second current source from said adjust node when said pulse control signal is in the inactive state.