FSA515 SPST Depletion Switch onsemi FSA515 Single-Pole Single Throw (SPST) Depletion Switch is a 5V high-performance switch with a negative swing. This depletion switch incorporates depletion technology that allows devices to conduct signals when there is no VDD available and to isolate signals when VDD is present. The 5.5V tolerant FSA515 depletion switch passes or isolates negative signal swings to -3V. This depletion switch IC is widely used in mobile accessories, adapters, cables, phones, tablets, laptops, and headsets.