Lamp tube driving circuit

Abstract

A lamp driving circuit with a floating power supply driver includes a microcomputing unit (20), a floating power supply driver (10) and a driving unit (30). The microcomputing unit (20) and the floating power supply driver (10) are either two independent integrated circuits or a single integrated circuit and manufactured under a normal voltage. The floating power supply driver (10) is coupled to the microcomputing unit (20) via two independent high-pressure coupling capacitors, instead of sharing the same ground with the microcomputing unit (20). The microcomputing unit (20) and the floating power supply driver (10) provide at least one low-voltage driving pulse output pin and one high-voltage driving pulse output pin to control the driving unit (30) so that a lamp connected to the driving unit (30) can be lit up.

Description

technical field [0001] The invention relates to a lamp tube drive circuit, in particular to a lamp tube drive circuit in which individual integrated circuit components manufactured by normal pressure processes respectively control high and low voltage side drive transistors. Background technique [0002] Please refer to Fig. 7, which is a driving circuit using a current transformer, which can be used to drive a gas discharge lamp 60. The circuit includes a bidirectional trigger switch 61 connected to the DC input terminal, a current transformer 62, two metal oxide The power transistors 63 and 64 are composed of material semiconductor field effect transistors (MOSFET). The primary side winding of the current transformer 62 is connected in series with the lamp tube 60, and its secondary side winding is connected with the aforementioned two power transistors 63, 64. LC circuit, the other end of the capacitor 66 is connected to the primary side winding of the current transforme...

AI Technical Summary

Problems solved by technology

In fact, inside the drive integrated circuit 70, there is a high-voltage coupling capacitor between the high-voltage output terminal Ho and the low-voltage output terminal Lo, and its withstand voltage must be as high as hundreds of volts. The driver integrated circuit 70 must consider the high-voltage process in terms of semiconductor raw material selection, internal component design, circuit layout, etc., so that the complexity of the process and the manufacturing cost will be relatively increased.

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