Patent ID: 7046040
Filing Date: 2006-05-16
Classification: H03F,H03K

Abstract:
1. A bootstrap driver, comprising: an output stage having an N-type high-side transistor and an N-type low-side transistor, which are arranged in series between a positive supply terminal and a negative supply terminal, an output of the driver being tapped from a common node between these transistors; a first control circuit for controlling the high-side transistor and a second control circuit for controlling the low-side transistor; a first voltage regulator having an output delivering a first supply voltage for said first control circuit, and a second voltage regulator having an output delivering a second supply voltage for said second control circuit, said first and second voltage regulators being mutually independent; a bootstrap capacitance arranged between the output of the driver and a boost-voltage node; a bootstrap diode having an anode connected to the output of the first voltage regulator and a cathode connected to the boost-voltage node; and a recovery diode having an anode connected to the output of the first voltage regulator and a cathode connected to the positive supply terminal, in order to conduct a reverse current of the bootstrap diode when the output of the driver switches from a low state, wherein the low-side transistor is on and the high-side transistor is off, to a high state wherein the low-side transistor is off and the high-side transistor is on.