Multiple RC triggered power supply clamp electro-static discharge (ESD) protective circuit

Abstract

The invention relates to the technical field of integrated circuit chip electro-static discharge protection, in particular to a multiple RC triggered power supply clamp electro-static discharge (ESD) protective circuit. The circuit detects access of static pulses through an ESD impact detecting unit and sends response signals to a tapping transistor to open a passage, the tapping transistor releases electrostatic charges carried by impacts and then the tapping transistor close the passage, and small leakage during normal electrification is guaranteed. Furthermore, a CR structure is used for replacing an RC+ inverter structure to serve as the ESD impact detecting unit, a circuit structure is simplified, and opening time of the tapping transistor is prolonged to some extent. Further, passive capacitance of the tapping transistor for closing the passage uses a current mirror unit, and opening time of the tapping transistor can be effectively prolonged. Therefore, the protective circuit can effectively prolong opening time of the tapping transistor under the ESD impact in a reasonable domain area and guarantees that leakage of the protective circuit during normal electrification is small.

Description

technical field [0001] The invention relates to the technical field of electrostatic discharge (ESD, Electronic Static Discharge) protection of integrated circuit chips, in particular to a multiple RC trigger power clamp ESD protection circuit. Background technique [0002] The electrostatic protection design of integrated circuit chips is one of the necessary conditions to ensure that the chip can work normally. If the chip does not have an effective anti-static shock mechanism, it is likely to fail due to electrostatic breakdown before it can function . During the production, transportation, testing and use of chips, they face many electrostatic shocks from mechanical equipment, human body or other electronic equipment. Therefore, electrostatic shock itself has different mechanisms and modes of occurrence. Generally speaking, electrostatic shock has the characteristics of short time and large instantaneous voltage and current, which has strong potential damage to the logi...

AI Technical Summary

Problems solved by technology

In the above-mentioned power supply clamp ESD protection circuit, the resistance of the off-path of the bleeder transistor is realized by PMOS transistors (Mp5, Mp6). resistance

Therefore, if the two-stage RC structure of the off-path of the bleeder transistor wants to achieve the equivalent time constant of the same size as the ESD impact detection resistor-capacitance structure, the capacitors C2 and C3 need to be made very large, and the larger passive devices make the protection The layout area of ​​the circuit is greatly increased. Therefore, the above-mentioned power clamp ESD protection circuit is contrary to the requirements of design reliability to a certain extent.

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