High-voltage enabling circuit for DC-DC converter

Abstract

Disclosed is a high-voltage enabling circuit for a DC-DC converter. The high-voltage enabling circuit comprises an internal power generation unit, a voltage detection unit and a comparison judgment unit, wherein the internal power generation unit is provided with a first high-voltage power input end, a first low-voltage power output end and a second low-voltage power output end; the voltage detection unit is provided with a first detection input end, a second detection input end and a first detection output end; the first detection input end is connected to an enabling pin, and the second detection input end is connected to the first low-voltage power output end; the comparison judgment unit is provided with a first comparison input end, a second comparison input end and a first comparisonoutput end; the first comparison input end is connected to the first detection output end; the second comparison input end is connected to the second low-voltage power output end, and the first comparison output end is connected to an analog module. The high-voltage enabling circuit enables a corresponding chip to be directly connected to a high-voltage power supply without using a special process, thereby reducing the process cost.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a high-voltage enabling circuit applied to a DC-DC converter. Background technique [0002] With the rapid development of semiconductor technology and microelectronics technology, DC-DC converters are widely used in consumer electronics, communication equipment, industrial applications, aerospace and other fields due to their high efficiency, wide load and fast response capabilities. [0003] According to the different application environments, the power supply range of the chip is also wider and wider, and the typical value is extended from the initial 3.3V, 5V and 12V to the current 18V or even 24V. [0004] In order to facilitate the electronic system to control the chip, the DC-DC converter usually has an external enable pin to control the operation and shutdown of the chip, so an enable circuit needs to be designed inside the chip. [0005] In general applications, the enable pin (E...

AI Technical Summary

Problems solved by technology

[0014] 1. Considering the limitation of the gate-source voltage of thin-gate oxide CDMOS, many chips have to limit the enable pin voltage to no more than 5V—but this connection method prevents the chip from being directly connected to a high-voltage power supply.

[0015] 2. Use a thick gate oxide process to improve the gate-source voltage withstand capability of the device, and the enable pin can be directly connected to a high-voltage power supply—but this method has a special process and relatively high cost

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