The CA3273 is a power IC equivalent of a P-N-P pass transistor operated as a high-side-driver current switch in either the saturated (ON) or cutoff (OFF) modes. The CA3273 incorporates circuitry to protect the pass currents, excessive input voltage, and thermal overstress. The high-side driver is intended for general purpose, automotive and potentially high-stress applications. If high-stress conditions exist, the use of an external zener diode of 35V or less between supply and load terminals may be required to prevent damage due to severe conditions (such as load dump, reverse battery and positive or negative transients). The CA3273 is designed to withstand a nominal reverse-battery (VBAT = 13V) condition without permanent damage to the IC. The CA3273 is supplied in a modified 3-lead TO-202 plastic power package.