Active Control of the Triggering Characteristics of NPN BJT, BSCR and NLDMOS-SCR Devices

This study presents a new solution for ESD protection of high-voltage and high-speed pins in power analog circuits, such as voltage switching regulators. A mixed device-circuit ESD solution is validated experimentally using transmission line pulse measurements. It is demonstrated that the triggering characteristics of both bipolar and MOS ESD devices can be successfully controlled as a function of operation mode in a large voltage range using an active circuit and control electrodes. An example of an active circuit to control the triggering characteristics of the ESD devices is presented. A practical implementation is verified for 50 V NPN BJT, Bipolar SCR and LDMOS-SCR snapback ESD devices. The advantage of the proposed solution over snapback ESD devices triggered by avalanche or displacement current is discussed for high-speed power analog applications.