Patent ID: 8981740
Filing Date: 2015-03-17
Classification: H02M

Abstract:
1. A multiple output switching circuit comprising: an input configured to receive power from a power source; a first output configured to provide a first output voltage; an inductor and a power switch connected between the input and first output; wherein the power switch is operable to transfer power from the input to the first output; a second output configured to provide a second output voltage; a second switch coupled between the first output and the second output; and a second switch controller configured to provide the second switch with a second switch control signal such that power is transferred from the input to the second output when the first output voltage level reaches a first output threshold level; wherein the second switch controller comprises: a first transistor that is configured to: a current mirror consisting of one or two transistors that are configured to conduct current to the second output and mirror a fraction of the current back to the first transistor to set the latch functionality for operating the second switch; wherein the current mirror is also configured to compare the current to the second output with a threshold level and reset the latch function when the current reaches the threshold level.