US Patent 12009657 ESD clamp circuit for low leakage applications

An ESD clamp circuit has an ESD detection circuit connected between a first terminal and a second terminal, with a first output node and a second output node. The ESD detection circuit is configured to output respective first and second control signals at the first and second output nodes in response to an ESD event. A discharge circuit includes a p-type transistor having a source, a drain and a gate, with the gate connected to the first output node. An n-type transistor has a source, a drain and a gate, with the gate connected to the second output node. The drain is connected to the drain of the p-type transistor. The discharge circuit is configured to establish a first ESD discharge path from the first terminal, through the p-type transistor and the n-type transistor, to the second terminal, and to further establish a second ESD discharge path in parallel with the first ESD discharge path. The second ESD discharge path includes a parasitic silicon controlled rectifier (SCR).