Dual-Input Linear Regulator Touts Auxiliary Control Circuit

A dual-input linear regulator with auxiliary control has been developed for providing a glitch-free 3.3V (±2%) output from a V_INPUT, V_STANDBY or 3.3V_AUX supply. The CS5233 linear regulator powers output loads directly when V_INPUT or V_STANDBY is available, or, alternately, V_AUX delivers power to a PFET that transmits its 3.3V supply to the load.
CS5233 IC replaces a two-diode, wired OR circuit that feeds a single input regulator, eliminating voltage headroom and threshold problems associated with channel switching diodes. In 8-lead narrow SOICs or 5-lead D²PAKs, the IC provides up to 500 mA or 1.5A, respectively, with 1 mV of line regulation and 5 mV of load regulation at 10 mA I_OUT. The 500-mA regulator costs $0.88 each/10K and the 1.5A regulator, $1.23.