SWITCHING REGULATOR
First Claim
1. A switching regulator control circuit for use in a switching regulator that converts an input voltage into an output voltage by switching of a switching device, the switching regulator control circuit generating a switching signal for controlling ON/OFF operation of the switching device, the switching regulator control circuit comprising:
- a fault detector configured to detect, based on a duty ratio of the switching signal or a variable correlated to the duty ratio and included in a control signal used to generate the switching signal, a fault state where the duty ratio falls outside a normal modulation range; and
a fault protector configured to stop the switching of the switching device when the fault detector detects the fault state,whereinthe fault detector is configured to detect the fault state when n or more pulses with a pulse width outside a normal range occur in the switching signal within m switching periods of normal operation (where n is a non-zero natural number less than or equal to m).
7 Assignments
0 Petitions
Accused Products
Abstract
A switching regulator control circuit is used in a switching regulator that converts an input voltage into an output voltage by the switching of a switching device, and generates a switching signal for controlling the ON/OFF operation of the switching device. The switching regulator control circuit has a fault detector and a fault protector. The fault detector detects, based on the duty ratio of the switching signal or a variable correlated to it and included in a control signal used to generate the switching signal, a fault state where the duty ratio falls outside the normal modulation range. The fault protector stops the switching of the switching device when the fault detector detects a fault state.
-
Citations
19 Claims
-
1. A switching regulator control circuit for use in a switching regulator that converts an input voltage into an output voltage by switching of a switching device, the switching regulator control circuit generating a switching signal for controlling ON/OFF operation of the switching device, the switching regulator control circuit comprising:
-
a fault detector configured to detect, based on a duty ratio of the switching signal or a variable correlated to the duty ratio and included in a control signal used to generate the switching signal, a fault state where the duty ratio falls outside a normal modulation range; and a fault protector configured to stop the switching of the switching device when the fault detector detects the fault state, wherein the fault detector is configured to detect the fault state when n or more pulses with a pulse width outside a normal range occur in the switching signal within m switching periods of normal operation (where n is a non-zero natural number less than or equal to m). - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A switching regulator control circuit for use in a switching regulator including:
-
a first switch having a first terminal thereof connected to a first application terminal to which an input voltage is applied; a second switch having a first terminal thereof connected to a second terminal of the first switch and having a second terminal thereof connected to a second application terminal to which a voltage lower than the input voltage is applied; and an overcurrent sensor configured to sense an overcurrent through the second switch, the switching regulator control circuit generating a switching signal for controlling ON/OFF operation of the first switch, wherein the switching regulator control circuit comprises; a fault detector configured to detect, based on a duty ratio of the switching signal or a variable correlated to the duty ratio and included in a control signal used to generate the switching signal, a fault state where the duty ratio falls outside a normal modulation range; and a fault protector configured to stop the switching of the first switch to turn the first switch OFF when the fault detector detects the fault state, wherein the switching regulator control circuit is configured to inhibit any pulse from occurring in the switching signal during a period in which an overcurrent is sensed by the overcurrent sensor. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
Specification