POWER SUPPLY WITH DYNAMIC INPUT CURRENT SUPPRESSION

摘要

A power supply is described, which comprises a first stage DC-to-DC voltage conversion block (100), and a second stage voltage conversion block (200) having a feedback circuit to regulate the output voltage (Vout) thereof so as to reduce changes in the output voltage as the output current (Iout) drawn by a load changes. The power supply also includes a capacitor (400) connected between the first and second stage voltage conversion blocks (100, 200) no supply current to the second stage voltage conversion block (200) when the input voltage (Vint) to the second stage voltage conversion block (200) changes due to changes in output current (Iout) of the second stage voltage conversion block (200). The first stage voltage conversion block (100) comprises a feedback circuit to regulate the output voltage of the first stage voltage conversion block (100) so as to reduce changes in the output, voltage as the input voltage (Vint) to the second stage voltage conversion block (200) changes due to changes in the output current (Iout) of the second stage voltage conversion block (200). The response of the feedback circuit of the first stage voltage conversion block (100) is slower than that of the feedback circuit of the second stage voltage conversion block (200). The first stage voltage conversion block (100) further comprises a rate-limiting circuit to regulate the rate of change of the output voltage of the first stage voltage conversion block (100) by the feedback circuit such that the rate of change of the input current (Iin to the first stage voltage conversion block (100) remains below a predetermined value.