Lighting tube drive device

Abstract

The invention relates to a lighting tube drive device for driving a plurality of light tube groups. The lighting tube drive device comprises a misphasing control circuit, a drive control circuit and a plurality of transformer circuits, wherein the drive control circuit comprises a plurality of switch circuits, a plurality of power switching circuits and a pulse width modulation (PWM) control circuit. The plurality of switch circuits are used for determining whether to output external voltage signals or not; the power switching circuits are correspondingly connected with the plurality of switching circuits, and are used for converting the external voltage signals to alternating current for outputting; the PWM control circuit is used for outputting the same PWM control signal to the plurality of power switching circuits; and the plurality of transformer circuits are correspondingly connected among the plurality of power switching circuits and the light tube groups so as to drive a plurality of lighting tubes. By adopting the lighting tube drive device, the use of synchronous circuits can be avoided, and the plurality of lighting tube groups can be respectively controlled by one PWM control circuit.

Description

technical field [0001] The invention relates to a lamp tube driving device, in particular to a driving device for a liquid crystal display (Liquid Crystal Display, LCD) lamp tube group. Background technique [0002] In a larger liquid crystal display (Liquid Crystal Display, LCD) panel, it is necessary to set multiple groups of lamp tubes in different areas to provide sufficient brightness, and the multiple groups of lamp tubes are driven by an inverter circuit (Inverter Circuit), which AC signal can be supplied to the lamp. Usually, multiple sets of control circuits are often provided in the inverter circuit for respectively controlling the lamp tube groups arranged in different areas, so as to drive multiple lamp tube groups respectively. [0003] Such as figure 1 The inverter circuit shown includes a plurality of transformer circuits 30 , a plurality of lamp tube groups 40 , a feedback circuit 50 , a phase-splitting control circuit 60 and a drive control circuit 10 . W...

AI Technical Summary

Problems solved by technology

[0004] However, in this lamp driving device, each lamp group needs to be controlled separately by a PWM control circuit, that is, the number of PWM control circuits must increase correspondingly according to the increase in the number of lamp groups, so the cost is relatively high

Simultaneously, a synchronous circuit needs to be set to make the operating frequencies of the plurality of PWM control circuits the same, thus resulting in complex circuits and low efficiency

Images