A Modified Zener Diode-Triggered Silicon Controlled Rectifier Used for 5V Application in 0.18um BCD Process

The modified Zener diode-triggered silicon controlled rectifier (MZDTSCR) is proposed in this paper. The MZDTSCR has low trigger voltage, suitable holding voltage, low leakage current and good electrostatic discharge (ESD) robustness. The physical mechanism and results analysis of the MZDTSCR are discussed. In addition, how do the trigger and holding voltages vary with the width increasing of the N+ bridge inside the MZDTSCR, are also analyzed. Test and simulation data show that MZDTSCR can be applied to the circuit with 5V operating voltage.