US 9,812,894 B2
Power switching circuit, semiconductor integrated circuit, radio apparatus, radio system, and power switching method
Satoshi Yamada, Kawasaki (JP)
Assigned to FUJITSU SEMICONDUCTOR LIMITED, Yokohama (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.