| 摘要 |
An ESD protection circuit incorporates an ESD shunt device triggered by an ESD trigger network. In non-powered situations, a first RC time constant in the ESD trigger network, corresponds with the time range of the onset an ESD event and controls application of the ESD shunt device in response to the ESD event. A second RC time constant in a shunt trigger network is selected to be longer than the first RC time constant and holds-off triggering of a shunt device during ESD shunt protection. When activated during powered-on operation, the shunt device shunts a resistive element in the ESD trigger network forming a third time constant. The shunt device guards against false triggering during noise on a power rail by maintaining the third time constant in the ESD trigger network. The third time constant ensures that power rail voltage buildup due to noise dissipates before a false trigger develops.
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