US 9,812,894 B2
Power switching circuit, semiconductor integrated circuit, radio apparatus, radio system, and power switching method
Satoshi Yamada, Kawasaki (JP)
Filed by FUJITSU SEMICONDUCTOR LIMITED, Yokohama-shi, Kanagawa (JP)
Filed on Mar. 16, 2015, as Appl. No. 14/658,946.
Claims priority of application No. 2014-086626 (JP), filed on Apr. 18, 2014.
Prior Publication US 2015/0303743 A1, Oct. 22, 2015
Int. Cl. H05K 7/14 (2006.01); H02J 7/04 (2006.01); G01R 31/40 (2014.01); G01R 19/00 (2006.01); H02J 7/02 (2016.01); H02J 50/10 (2016.01)
CPC H02J 7/045 (2013.01) [G01R 19/0038 (2013.01); G01R 31/40 (2013.01); G01R 19/0092 (2013.01); H02J 7/025 (2013.01); H02J 50/10 (2016.02)] 14 Claims
OG exemplary drawing
1. A power switching circuit comprising:
a current mirror circuit configured to generate a plurality of mirror currents, by transferring, at different mirror ratios, a plurality of monitored currents that are obtained by monitoring a plurality of power supply voltages;
a selector configured to select the plurality of mirror currents by a combination of the different mirror ratios at which the plurality of monitored currents are transferred, according to a switching state of the plurality of power supply voltages;
a comparator, included in the current mirror circuit, and configured to compare the plurality of mirror currents selected by the selector, and output a comparison result; and
a switching circuit configured to switch a supply voltage to be supplied to a load to one of the plurality of power supply voltages, based on the comparison result.