Single-Event Transient Testing of Low Dropout PNP Series Linear Voltage Regulators

Recommendations are provided for Single Event Transient (SET) testing of low dropout (LDO) PNP series linear voltage regulators. A combination of SPICE circuit simulations and pulsed laser irradiations are used to demonstrate that the equivalent series resistance (ESR), loading conditions and regulator stability are the key elements that govern LDO regulator´s SET response. Pulsed laser testing of several light-like candidates shows similar SET trends and dependences. Due to the additional circuits introduced in an LDO design, we reveal the existence of a thermal shutdown mode that can be triggered by a single event that is also load dependent.