Analog Devices

TheLTC4372/LTC4373 are positive high voltage ideal diode controllers that drive an external N-channel MOSFET to replace a Schottky diode. They control the forward voltage drop across the MOSFET to ensure current delivery or current transfer from one path to the other even at light loads.A 5μA operating current achieves high efficiency for intermittent load applications or always-on backup power supplies. If a power source fails or is shorted, a fast turn-off minimizes reverse current transients. The LTC4372/LTC4373 control back-to-back N-channel MOSFETs for inrush current control and load switching.The LTC4372’s SHDN pin keeps the MOSFET off and reduces the quiescent current to 3.5μA. The LTC4373 has a UV pin for undervoltage monitoring while theUVOUTpin provides hysteresis adjustment and status information. During undervoltage, the back-to-back MOSFETs are cut off and quiescent current reduces to 0.5μA.APPLICATIONSAutomotive Battery ProtectionRedundant Power SuppliesPortable InstrumentationSolar Powered SystemsEnergy Harvesting ApplicationsSupply Holdup

The LTC4376 is a 7A ideal diode that uses an internal 15mΩ N-channel MOSFET to replace a Schottky diode when used in diode-OR and high current diode applications. The LTC4376 reduces power consumption, heat dissipation and PC board area.The LTC4376 controls the forward voltage drop across the internal MOSFET to ensure smooth current delivery without oscillation even at light loads. If a power source fails or is shorted, a fast turn-off minimizes reverse current transients. The LTC4376 also easily ORs power sources to increase total system reliability.With its low operating voltage, small solution size and the ability to withstand reverse input voltage, the LTC4376 excels in portable battery applications. A shutdown mode is available to reduce the quiescent current to 9μA. TheSHDNpin can also control the forward current path when an external MOSFET is used in series with the internal MOSFET in a back-to-back configuration.ApplicationsAutomotive Battery ProtectionRedundant Power SuppliesPortable Battery DevicesComputer Systems/Servers

The LTC4380 low quiescent current surge stopper protects loads from high voltage transients. Overvoltage protection is provided by clamping the gate voltage of an external N-channel MOSFET to limit the output voltage to a safe value during overvoltage events such as load dump in automobiles. Fixed gate clamp voltages are selectable for 12V and 24V/28V systems. For systems of any voltage up to 72V, use the adjustable gate clamp versions. Overcurrent protection is also provided.An internal multiplier generates a TMR pin current proportional to VDSand ID, so that operating time in both overcurrent and overvoltage conditions is limited in accordance with MOSFET stress.The GATE pin can drive back-to-back MOSFETs for reverse input protection, eliminating the voltage drop and dissipation of a Schottky diode solution. A low 8µA operating current permits use in always-on and battery powered applications. An accurate ON pin comparator monitors the input supply for undervoltage (UV) conditions and also serves as a shutdown input, reducing the quiescent current to 6µA.ApplicationsAutomotive/Avionic/Industrial Surge ProtectionHot Swap, Live InsertionHigh Side Switch for Battery Powered SystemsAutomotive Load Dump Protection

The LTC4410 enables simultaneous battery charging and operation of portable USB 1.0 and 2.0 compliant devices while they are connected to a USB port. As the USB peripheral load increases, the LTC4410 proportionally reduces the battery charge current to keep the total current less than 500mA or 100mA, depending on the state of the MODE pin.The LTC4410 includes a USB present output that drives an external P-channel MOSFET to disconnect the battery from the USB peripheral when the USB power is valid. This allows device operation when connected to the USB port, even when the battery is deeply discharged.Other features include reverse current blocking, thermal shutdown and low quiescent current (80µA in 500mA MODE) that is compliant with USB Suspend Mode.The LTC4410 is available in the low profile (1mm) SOT-23 (ThinSOT™) package.ApplicationsCellular PhonesPDAsDigital CamerasMP3 PlayersBattery Backup Systems

The LTC4412HV controls an external P-channel MOSFET to create a near ideal diode function for power switchover or load sharing. This permits highly efficient OR’ing of multiple power sources for extended battery life and low selfheating. When conducting, the voltage drop across the MOSFET is typically 20mV. For applications with a wall adapter or other auxiliary power source, the load is automatically disconnected from the battery when the auxiliary source is connected. Two or more LTC4412HVs may be interconnected to allow load sharing between multiple batteries or charging of multiple batteries from a single charger. The LTC4412HV is an extended supply and temperature range version of the LTC4412.The wide supply operating range supports operation from one to eight Li-Ion cells in series. The low quiescent current (11µA typical) is independent of the load current. The gate driver includes an internal voltage clamp for MOSFET protection.The STAT pin can be used to enable an auxiliary P-channel MOSFET power switch when an auxiliary supply is detected. This pin may also be used to indicate to a microcontroller that an auxiliary supply is connected. The control (CTL) input enables the user to force the primary MOSFET off and the STAT pin low.The LTC4412HV is available in a low profile (1mm) SOT-23 package.Supply RangeLTC44122.5V - 28V (36V max)LTC4412HV2.5V - 36V (40V max)ApplicationsIndustrial and Automotive ApplicationsNotebook and Handheld ComputersUSB-Powered PeripheralsUninterruptible Power SuppliesLogic Controlled Power Switch

The LTC4413-1 and LTC4413-2 each contain two monolithic ideal diodes, each capable of supplying up to 2.6A from input voltages between 2.5V and 5.5V. The ideal diodes use a 100mΩ P-channel MOSFET to independently connect INA to OUTA and INB to OUTB. During normal forward operation, the voltage drops across each of these diodes are regulated to as low as 18mV. Quiescent current is less than 80µA for diode currents up to 1A. If either of the output voltages exceeds its respective input voltage, that MOSFET is turned off and less than 1µA of reverse current flows from OUT to IN. Maximum forward current in each MOSFET is limited to a constant 2.6A and internal thermal limiting circuits protect the part during fault conditions. An internal overvoltage protection sensor detects when a voltage exceeds the LTC4413-2 absolute maximum voltage tolerance.Two active-high control pins independently turn off the two ideal diodes contained within the LTC4413-1/LTC4413-2. When the selected channel is reverse biased, or the LTC4413-1/LTC4413-2 is put into low power standby, the status signal is pulled low by an 11µA open drain.The LTC4413-1/LTC4413-2 are housed in a 10-lead 3mm × 3mm DFN package.FeaturesLTC4413Lower IqLTC4413-1Lower Vfwd, Faster Response, Higher IqLTC4413-2Lower Vfwd, Faster Response, Higher Iq, 13V (max) OVPApplicationsBattery and Wall Adapter Diode OR’ing in Handheld ProductsBackup Battery Diode OR’ingPower SwitchingUSB PeripheralsUninterruptable Supplies

The LTC4414 controls an external P-channel MOSFET to create a near ideal diode function for power switchover. This permits highly efficient OR’ing of multiple power sources for extended battery life and low self- heating. When conducting, the voltage drop across the MOSFET is typically 20mV. For applications with a wall adapter or other auxiliary power source, the load is automatically disconnected from the battery when the auxiliary source is connected. Two or more LTC4414s may be interconnected to allow switchover between multiple batteries or charging of multiple batteries from a single charger.The wide supply operating range supports operation from one to eight Li-Ion cells in series. The low quiescent current (30µA typical) is independent of the load current. The gate driver includes an internal voltage clamp for MOSFET protection.The STAT pin can be used to enable an auxiliary P-channel MOSFET power switch when an auxiliary supply is detected. This pin may also be used to indicate to a microcontroller that an auxiliary supply is connected. The control (CTL) input enables the user to force the primary MOSFET off and the STAT pin low.The LTC4414 is available in a low profile 8-lead MSOP package.ApplicationsHigh Current Power Path SwitchIndustrial and Automotive ApplicationsUninterruptable Power SuppliesLogic Controlled Power SwitchBattery Backup SystemsEmergency Systems with Battery Backups

The LTC4415 contains two monolithic PowerPath ideal diodes, each capable of supplying up to 4A with typical forward conduction resistance of 50mΩ. The diode voltage drops are regulated to 15mV during forward conduction at low currents, extending the power supply operating range and ensuring no oscillations during supply switchover. Less than 1μA of reverse current flows from OUT to IN making this device well suited for power supply ORing applications.The two ideal diodes are independently enabled and prioritized using inputs EN1 andEN2. The output current limits can be adjusted independently from 0.5A to 4A using resistors on the CLIM pins. Furthermore, the ideal diode currents can be monitored via CLIM pin voltages.Open-drain status pins indicate when the ideal diodes are forward conducting. When the die temperature approaches thermal shutdown, or if the output load exceeds the current limit threshold, the corresponding warning pins are pulled low.ApplicationsHigh Current PowerPath™SwitchBattery and Wall Adapter Diode ORingBackup Battery Diode ORingLogic Controlled High Current Power SwitchSupercapacitor ORingMultiple Battery Sharing

The LTC4416/LTC4416-1 control two sets of external P-channel MOSFETs to create two near ideal diode functions for power switchover circuits. This permits highly efficient OR’ing of multiple power sources for extended battery life and low self heating. When conducting, the voltage drop across the MOSFET is typically 25mV. For applications with a wall adapter or other auxiliary power source, the load is automatically disconnected from the battery when the auxiliary source is connected.The LTC4416 integrates two interconnected PowerPath™controllers with soft switchover control. The "soft-off" switchover permits the users to transfer between two dissimilar voltages without excessive voltage undershoot (or VDROOP) in the output supply. The LTC4416/LTC4416-1 also contain a "fast-on" feature that dramatically increases gate drive current when the forward input voltage exceeds 25mV. The LTC4416 "fast off" feature is engaged when the sense voltage exceeds the input voltage by 25mV. The LTC4416-1 enables the fast off under the same conditions and when the other external P-channel device is selected using the enable pins.The wide operating supply range supports operation from one to eight Li-Ion cells in series. The low quiescent current (35μA per channel) is independent of the load current. The gate driver includes an internal voltage clamp for MOSFET protection.The LTC4416/LTC4416-1 are available in low profile 10-lead MSOP packages.ApplicationsHigh Current PowerPath SwitchIndustrial and Automotive ApplicationsUninterruptible Power SuppliesLogic Controlled Power SwitchBattery Backup SystemEmergency Systems with Battery Backups