Electrostatic discharge (ESD) protection circuit including an avalanche semiconductor controlled rectifier (SCR) with parallel connected static trigger control circuit (TCC)

An electrostatic discharge (ESD) protection circuit, comprising:

• a first semiconductor controlled rectifier (SCR) device of two terminal, self-turn on, type consisting of an anode terminal and a cathode terminal, and wherein said first SCR device has an avalanche breakdown voltage for self-turn on;
• wherein said avalanche breakdown voltage is set by a breakdown avalanche of a PN junction of the first SCR device;
• wherein the first SCR device includes an NPN-type bipolar transistor coupled to a PNP-type bipolar transistor, and wherein said PN junction of the first SCR device is a junction between a collector and base of the NPN-type bipolar transistor;
• a first circuit path having a first node and a second node, and wherein said first circuit path has an activation voltage for turn on;
• wherein the first SCR device and first circuit path are connected in parallel with the anode terminal and the first node coupled to a first pin and with the cathode terminal and the second node coupled to a second pin;
• wherein said activation voltage is less than the avalanche breakdown voltage;
• wherein the first circuit path comprises a series connected chain of M Zener diodes that are coupled between the anode terminal and the cathode terminal of the first SCR device, with each Zener diode has a size N greater than or equal to 20, where N is a number of diode structures connected in parallel for each Zener diode.