SWITCHING REGULATOR

• US 20150061615A1
• Filed: 08/18/2014
• Published: 03/05/2015
• Est. Priority Date: 08/27/2013
• Status: Active Grant

• Current Assignee: Nisshinbo Micro Devices Incorporated
• Original Assignee: Ricoh Company Limited
• Inventors: Michishita, Yuusuke
• Granted Patent: US 9,431,907 B2
• Time in Patent Office: Days
• US Class Current: 323/271
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A switching regulator includes a first switching element and a second switching element in a pair to be switched over to convert an input voltage to a certain constant voltage, and an operation monitor to monitor an operation state of the first switching element, in which a switching of the second switching element is changed according to a result of the monitoring by the operation monitor.

Claims

1. A switching regulator comprising:

a first switching element and a second switching element in a pair to be switched over to convert an input voltage to a certain constant voltage; and

an operation monitor to monitor an operation state of the first switching element, wherein

a switching of the second switching element is changed according to a result of the monitoring by the operation monitor.

2. The switching regulator according to claim 1, wherein

the operation monitor is an on-time determiner circuit to determine whether or not an ON time of the first switching element has reached a preset determination time.

3. The switching regulator according to claim 1, further comprising

a smoothing circuit including an inductor and a condenser, to smoothen an output voltage, wherein

the operation monitor is an inductor current determiner circuit to determine whether not a value of current flowing into the inductor has reached a preset determination value.

4. The switching regulator according to claim 2, wherein

when the on-time determiner circuit determines that the ON time of the first switching element has reached the preset determination time, the first switching element is turned off and the second switching element is not turned on.

5. The switching regulator according to claim 3, wherein

when the inductor current determiner circuit to determine that the current value has not reached the preset determination value, the first switching element is turned off and the second switching element is not turned on.

6. The switching regulator according to claim 2, further comprising

at least two off-time setters to determine a timing at which the second switching element is turned off, wherein

one of the off-time setters is selected according to a result of the determination of the ON time of the first switching element by the on-time determiner circuit, and the second switching element is turned off in accordance with the selected off-time setter.

7. The switching regulator according to claim 3, further comprising

at least two off-time setters to determine timing at which the second switching element is turned off, wherein

one of the off-time setters is selected according to a result of the determination of the current value of the inductor by the inductor current determiner circuit, and the second switching element is turned off in accordance with the selected off-time setter.

8. The switching regulator according to claim 6, wherein

one of the off-time setters is an on-time setting circuit to detect that a time for which the second switching element is placed in an ON state has reached a preset ON time.

9. The switching regulator according to claim 7, wherein

one of the off-time setters is an on-time setting circuit to detect that a time for which the second switching element is placed in an ON state has reached a preset ON time.

10. The switching regulator according to claim 8, wherein

the on-time is changed in accordance with an input voltage or an output voltage.

11. The switching regulator according to claim 9, wherein

the on-time is changed in accordance with an input voltage or an output voltage.