| US 7,576,531 B2 | ||
| Switching regulator and electronic device therewith | ||
| Hirotaka Nakabayashi, Kyoto (Japan) | ||
| Assigned to Rohm Co., Ltd., Kyoto (Japan) | ||
| Appl. No. 11/908,314 PCT Filed Mar. 14, 2006, PCT No. PCT/JP2006/304985 § 371(c)(1), (2), (4) Date Sep. 11, 2007, PCT Pub. No. WO2006/103912, PCT Pub. Date Oct. 05, 2006. |
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| Claims priority of application No. 2005-090479 (JP), filed on Mar. 28, 2005. | ||
| Prior Publication US 2009/0066304 A1, Mar. 12, 2009 | ||
| Int. Cl. G05F 1/573 (2006.01); G05F 1/575 (2006.01) | ||
| U.S. Cl. 323—285 [323/284] | 4 Claims |
| 1. A switching regulator comprising:
an output switching element connected between an input terminal to which an input voltage is applied and an output terminal
from which an output voltage is derived to be fed to a load;
an output feedback circuit generating an error voltage varying according to an error between an actual value of and a target
value of the output voltage;
a switching control circuit turning on and off the output switching element based on the error voltage so that the error of
the output voltage is reduced;
a short-circuit current protection circuit including:
a first comparator comparing with a predetermined first threshold voltage an output current reference voltage varying according
to an output current to the load,
the short-circuit current protection circuit generating, based on a comparison output signal from the first comparator, a
short-circuit current protection signal instructing whether to drive the switching control circuit; and
a drive current generating circuit including:
a second comparator operating with a drive current lower than a drive current for the first comparator and comparing the error
voltage with a predetermined second threshold voltage,
the drive current generating circuit determining, based on a comparison output signal from the second comparator, whether
to supply the drive current to the first comparator.
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