Anti-noise jamming high-side drive circuit

Abstract

The invention discloses an anti-noise jamming high-side drive circuit, which comprises a floating power supply, a double-pulse generation circuit, a high-voltage level shift circuit, an undervolatge detection circuit, an RS trigger circuit, a gate drive circuit and a noise cancellation circuit, wherein the noise cancellation circuit consists of a common mode voltage detection circuit, a common mode noise cancellation circuit and an offset noise cancellation circuit which are sequentially connected; the two input ends of the noise cancellation circuit are connected with the two output ends of the high-voltage level shift circuit; the noise cancellation circuit receives high-voltage equidirectional control signals from the high-voltage level shift circuit, cancels floating noises in the high-voltage equidirectional control signals and outputs setting signals and resetting signals; and the setting signal output end of the noise cancellation circuit is connected with the XS input end of the RS trigger circuit, while a resetting signal output end is connected with the XR input end of the RS trigger circuit. The anti-noise jamming high-side drive circuit cancels the floating noises generated by the floating of the high-side power supply, has low power consumption and simple circuit structure, saves the area of a chip and is conveniently popularized and used.

Description

technical field [0001] The invention belongs to the technical field of design of high-end drive circuits in power MOS gate integrated circuits, and in particular relates to a high-end drive circuit resistant to noise interference. Background technique [0002] Almost all domestic electronic ballasts use traditional transformers to drive half-bridge inverter circuits. As we all know, in an electronic ballast driven by a transformer, two power transistors connected in a push-pull type are not only used as a switch, but also an important active component in an oscillating circuit. This kind of high-frequency oscillator, which relies on pulse transformer coupling, needs a trigger circuit composed of a resistor, a start-up capacitor and a bidirectional diode to start "so as to establish oscillation. The phase-opposite pulses generated by the secondary coil of the transformer drive two power tubes" to make Its alternate saturated conduction "so as to output high-frequency voltage...

AI Technical Summary

Problems solved by technology

[0004] Since the high-end circuit is powered by a floating power supply, there will be floating noise on the line connected to the high-voltage floating power supply in the high-end circuit. The most prominent and most destructive is the output signal of the high-voltage level shift circuit. The influence of level shift on the large parasitic capacitance of the tube, and due to the incomplete matching of the high-voltage level shift circuit caused by the process, the output signal of the high-voltage level shift circuit will have large common mode noise and offset noise, which will cause Cause the high-end circuit to be triggered by mistake, thus destroying the normal operation of the high-end circuit

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