Patent ID: 9557805
Date: 2017-01-31
CPC Classifications: G06F,H02J

Claim:
1. A power management circuit comprising: a first terminal configured to be coupled to an electric power generation source; a second terminal configured to be coupled to a load to be powered; a third terminal configured to be coupled to a battery; a linear regulator coupled between the first terminal and the second terminal; a first comparator having its input coupled to the first terminal and its output coupled to an input terminal of the linear regulator, the first comparator configured to activate the linear regulator when a voltage level of said electric power generation source is greater than a first threshold; a first switch coupled between an output terminal of the linear regulator and the second terminal; a controllable current source coupled between the output terminal and the third terminal and configured to be activated by a signal provided by the linear regulator when current in the linear regulator is detected; a second switch coupled between the output terminal and the third terminal and configured to be activated by the signal when the controllable current source is deactivated to couple the battery to the output terminal; and a second comparator having a first input coupled to the third terminal and a second input coupled to a reference and its output coupled to the first switch.