A power management chip and display device

Abstract

The invention provides a power management chip and a display device. The power management chip includes a level conversion unit, a pulse width modulation unit, and a power-down protection circuit. The power-down protection circuit includes: a voltage divider circuit unit, a detection circuit unit, and a power-down protection unit. The voltage divider circuit unit is used for The detection voltage is obtained by dividing the voltage output by the drive chip of the display panel, the detection circuit unit is used to compare the detection voltage with the reference voltage, and output a discharge enable control signal to the level conversion unit, the The power-down protection unit is used for jointly controlling the enable terminal of the pulse width modulation unit according to the level of the discharge enable control signal and the level of the enable control signal of the pulse width modulation unit. By increasing the detection of the input voltage, the invention avoids abnormal linkage between the level conversion unit and the pulse width modulation unit, resulting in abnormal output of the pulse width modulation unit when the voltage drops abnormally and recovers rapidly.

Description

technical field [0001] The invention relates to the field of display technology, in particular to a power management chip and a display device. Background technique [0002] At present, various protection circuits are installed in the power management chip of the display device. There are mainly over-voltage protection circuits, over-current protection circuits, and under-voltage protection circuits for output, but there are few protections for input, mainly under-voltage protection. and overcurrent protection etc. [0003] In the process of using the display device, it is often encountered that the voltage drops abnormally, such as the abnormal jump of the mains power, poor contact, etc. When the input voltage loses power, the level conversion unit will trigger the discharge function, that is, the level conversion unit All the voltages of the module are converted to high level and start to discharge. At this time, if the voltage returns to normal quickly, the output of oth...

AI Technical Summary

Problems solved by technology

[0005] An embodiment of the present invention provides a power management chip, which is used to solve the problem of display devices in the prior art. Due to the large capacitance of the panel, when the voltage drops abnormally and recovers quickly, it takes time to switch the level of the level conversion unit, resulting in The abnormal timing in the power management chip triggers the overcurrent protection of the power management chip, resulting in technical problems such as power failure of the display device and abnormal display screen

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