LT4356MPS-2#PBF

LT4356MPS-2#PBF FEATURES

Linear Regulator Controller

LT4356MPS-2#PBF DESCRIPTION

The LT®4356 surge stopper protects loads from high volt-age transients. It regulates the output during an overvolt-age event, such as load dump in automobiles, by control-ling the gate of an external N-channel MOSFET. The outputis limited to a safe value thereby allowing the loads tocontinue functioning. The LT4356MP also monitors thevoltage drop between the VCC and SNS pins to protectagainst overcurrent faults. An internal amplifier limits thecurrent sense voltage to 50mV. In either fault condition, atimer is started inversely proportional to MOSFET stress.If the timer expires, the FLT pin pulls low to warn of animpending power-down. If the condition persists, theMOSFET is turned off. After a cooldown period, the GATEpin pulls up turning on the MOSFET again.The auxiliary amplifier may be used as a voltage detectioncomparator or as a linear regulator controller driving anexternal PNP pass transistor.Back-to-back FETs can be used in lieu of a Schottky diodefor reverse input protection, reducing voltage drop andpower loss. A shutdown pin reduces the quiescent currentto less than 7µA for the LT4356-1 during shutdown. TheLT4356-2 differs from the LT4356-1 during shutdown byreducing the quiescent current to 60µA and keeping alivethe auxiliary amplifier for uses such as an undervoltagelockout or always-on regulator.Overvoltage Protector Regulates Output at27V During Transient

LT4356MPS-2#PBF APPLICATIONS