SEMICONDUCTOR DEVICE
First Claim
1. A semiconductor device for driving a high-side switching device and a low-side switching device ON and OFF in a complementary manner, the high-side switching device and the low-side switching device being totem pole-connected with a node therebetween to be connected to a load to drive the load, the semiconductor device comprising:
- a high-side driver circuit and a low-side driver circuit which respectively switch the high-side switching device and the low-side switching device ON and OFF in a complementary manner;
a bootstrap capacitor connected to a power supply that supplies driving power to the low-side driver circuit via a diode such that the bootstrap capacitor is charged when the low-side switching device is ON, and a resulting charge voltage is boosted and applied to the high-side driver circuit when the low-side switching device is OFF;
a supplementary bootstrap capacitor connected in parallel to the bootstrap capacitor via a switch circuit such that the supplementary bootstrap capacitor is charged by an intermediate voltage at an intermediate node between the high-side and low-side driver circuits that is to be connected to said node between the high-side switching device and the low-side switching device when the high-side switching device is ON;
a Zener diode that is connected to said intermediate node and that regulates a charging voltage of the supplementary bootstrap capacitor; and
a control circuit that controls the switch circuit so as to apply a charge voltage of the supplementary bootstrap capacitor to the high-side driver circuit when the charge voltage of the bootstrap capacitor decreases to less than a prescribed voltage while the high-side switching device is ON.
1 Assignment
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Accused Products
Abstract
A semiconductor device includes: a bootstrap capacitor charged via a diode when a low-side switching device is ON, a resulting charge voltage being applied to a high-side driver circuit when the low-side switching device is OFF; a supplementary bootstrap capacitor charged when the low-side switching device is OFF; a Zener diode that regulates a charge voltage of the supplementary bootstrap capacitor; and a control circuit that applies the charge voltage of the supplementary bootstrap capacitor to the high-side driver circuit via a switch circuit when the charge voltage of the bootstrap capacitor decreases to less than a prescribed voltage while a high-side switching device is ON.
8 Citations
11 Claims
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1. A semiconductor device for driving a high-side switching device and a low-side switching device ON and OFF in a complementary manner, the high-side switching device and the low-side switching device being totem pole-connected with a node therebetween to be connected to a load to drive the load, the semiconductor device comprising:
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a high-side driver circuit and a low-side driver circuit which respectively switch the high-side switching device and the low-side switching device ON and OFF in a complementary manner; a bootstrap capacitor connected to a power supply that supplies driving power to the low-side driver circuit via a diode such that the bootstrap capacitor is charged when the low-side switching device is ON, and a resulting charge voltage is boosted and applied to the high-side driver circuit when the low-side switching device is OFF; a supplementary bootstrap capacitor connected in parallel to the bootstrap capacitor via a switch circuit such that the supplementary bootstrap capacitor is charged by an intermediate voltage at an intermediate node between the high-side and low-side driver circuits that is to be connected to said node between the high-side switching device and the low-side switching device when the high-side switching device is ON; a Zener diode that is connected to said intermediate node and that regulates a charging voltage of the supplementary bootstrap capacitor; and a control circuit that controls the switch circuit so as to apply a charge voltage of the supplementary bootstrap capacitor to the high-side driver circuit when the charge voltage of the bootstrap capacitor decreases to less than a prescribed voltage while the high-side switching device is ON. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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Specification