A Single-Event Latchup setup for high-precision AMS circuits

One of the most critical radiation effects, because it is potentially destructive, is the Single-Event Latchup (SEL). Positive feedback in parasitic bipolar structures, triggered by a current pulse induced by an ionizing particle, creates a low impedance path between supply and ground. If the supply is not rapidly shut down, high currents can cause burnout or metal opens. Any radiation campaign must thus implement some protection at the board level to properly detect the onset of a latchup and shut the circuit power down. This paper describes an SEL detection platform, designed for a 13b 40Msps ADC prototype, that takes into account the specific requirements of high-precision Analog and Mixed-Signal circuits.