Protection circuit for preventing load switch from thermal damage

Abstract

The invention provides a protection circuit for preventing a load switch from thermal damage, wherein a plurality of branches are connected in parallel; in each parallel connected branch, one end of acurrent source IDC is connected to the input end VCC of the power source, the other end of the current source IDC is connected to one end of an inverter INV and the collector of a transistor, the base of the transistor is connected to the positive end of a voltage source VDC, the emitter of the transistor is grounded, and the other end of a reflector is connected to the input end of the gate OR.The protection circuit provided by the invention can accurately detect temperature changes in multiple directions due to many selected points around the power tube, and real-time detection can be carried out when temperature changes occur at any part of the power tube. The number of temperature sensors is selected according to the specific situation in the circuit, and the temperature sensors arearranged around the power tube in a certain sorting method, which can more effectively control the internal temperature of the chip to protect the chip.

Description

technical field [0001] The invention relates to the field of protection circuits, in particular to a protection structure and method for preventing burnout by heat. Background technique [0002] With the continuous integration of chips, high-power devices are often used in power management chips, which have strict requirements on the temperature of the chip to prevent accidents that cause the chip to burn due to excessive temperature. At present, most chips use a built-in temperature sensor inside the chip to detect the temperature of the power tube to prevent the power tube from being burned due to excessive temperature. However, there are some problems in the current technical method, such as figure 1 As shown, the solid line box is the schematic diagram of the position of the power tube, and the dotted line box is the schematic diagram of the position of the temperature sensor. Generally, the temperature sensor is placed on one side of the power tube for temperature dete...

AI Technical Summary

Problems solved by technology

However, there are some problems in the current technical method, such as figure 1 As shown, the solid line box is the schematic diagram of the position of the power tube, and the dotted line box is the schematic diagram of the position of the temperature sensor. Generally, the temperature sensor is placed on one side of the power tube for temperature detection. Since the power tube occupies a large area in the chip, The temperature of each part is different. Generally, the temperature in the center of the power tube is higher than the temperature on both sides. However, since the temperature sensor can only detect the temperature on one side of the power tube, it cannot detect the real temperature inside the power tube. deviation, which may also burn the power tube

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