SD protection circuit for MIM capacitor

Abstract

Provided in the invention is an ESD protection circuit for an MIM capacitor. The ESD protection circuit comprises N FETs that are connected in sequence of from D poles to S poles; G poles of the FETsare grounded; and the S pole of the first FET is connected to one end of an MIM capacitor and the D pole of the Nth FET is connected to the other end of the MIM capacitor, so that the ESD protection circuit formed by series connection of the N FETs is connected in parallel with the MIM capacitor needing protection. When the voltage, generated by electrostatic discharging, of the MIM capacitor is too large, the current flows through the ESD protection circuit to protect the MIM capacitor. In addition, the invention also provides a radio-frequency switching device with the ESD protection circuitof the MIM capacitor; and because the a radio-frequency switching device can withstand the high ESD voltage, so that the reliability is improved.

Description

technical field [0001] The invention belongs to the field of integrated circuit design, in particular to a MIM capacitance ESD protection circuit in radio frequency and microwave integrated circuits. Background technique [0002] Electrostatic discharge (ESD) issues are a difficult problem in integrated circuit design. There are different standard levels of ESD, and integrated circuit design generally requires 2kV protection capability under the HBM (human body) model. MIM capacitors (on-chip metal-insulator-metal capacitors) have the following limitations in use: MIM capacitors connected in series on the ESD path will reduce the ESD level of the entire chip. [0003] The breakdown voltage (BVcap) of the MIM capacitor is mostly in the range of 30-50V. The equivalent circuit of capacitors in series on the ESD path, such as figure 1 As shown, the electrostatic discharge path with MIM capacitors in series can withstand the maximum ESD voltage (Vesd) to satisfy the following ...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to solve the problem that the MIM capacitor connected in series to the ground on the electrostatic discharge path is broken down due to electrostatic discharge, without the need to use a large-area MIM capacitor and without affecting other circuit performances

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