Analog Devices

The LTC4331 is a point-to-point SMBus compatible I2C slave device extender designed for operation in high noise industrial environments. Using a ±60V fault protected differential transceiver, the LTC4331 can extend an I2C/SMBus bus, including SMBALERT and a control signal, over a single twisted pair differential link up to 1200m. With an extended common mode operating range the solution provides tolerance to large ground differences between nodes. For EMI sensitive environments, a slew rate control pin reduces the EMI emitted from the differential link.In addition, the LTC4331 can act as an I2C to I2C bridge allowing independent bus frequencies between the local and remote networks. The solution is completely transparent to the master requiring no additional code in most cases; however, a control interface is provided for additional configuration and fault monitoring.A master controller fully supporting SCL clock-stretching is strongly recommended.APPLICATIONSIndustrial Control and SensorsLighting and Sound System Control

The LTC4350 is a load share controller that allows systems to equally load multiple power supplies connected in parallel. The output voltage of each supply is adjusted using the SENSE+input until all currents match the share bus. The LTC4350 also isolates supply failures by turning off the series pass transistors and identifying the failed supply. The failed supply can then be removed and replaced with a new unit without turning off the system power. The LTC4350 is available in a 16-pin narrow SSOP package.ApplicationsServers and Network EquipmentTelecom and Base Station EquipmentDistributed Power Systems

The LTC4352 creates a near-ideal diode using an external N-channel MOSFET. It replaces a high power Schottky diode and the associated heat sink, saving power and board area. The ideal diode function permits low loss power ORing and supply holdup applications.The LTC4352 regulates the forward voltage drop across the MOSFET to ensure smooth current transfer in diode-OR applications. A fast turn-on reduces the load voltage droop during supply switch-over. If the input supply fails or is shorted, a fast turn-off minimizes reverse currents.The controller operates with supplies from 2.9V to 18V. For lower voltages, an external supply is needed at the VCCpin. Power passage is disabled during undervoltage or overvoltage conditions. The controller also features an open MOSFET detect circuit that flags excessive voltage drop across the pass transistor in the on state. A REV pin enables reverse current, overriding the diode behavior when desired.ApplicationsRedundant Power SuppliesSupply HoldupTelecom InfrastructureComputer Systems and Servers

The LTC4353 controls external N-channel MOSFETs to implement an ideal diode function. It replaces two high power Schottky diodes and their associated heat sinks, saving power and board area. The ideal diode function permits low loss power supply ORing and supply holdup applications.The LTC4353 regulates the forward-voltage drop across the MOSFET to ensure smooth current transfer in diode-OR applications. A fast turn-on reduces the load voltage droop during supply switchover. If the input supply fails or is shorted, a fast turn-off minimizes reverse-current transients.The controller operates with supplies from 2.9V to 18V. If both supplies are below 2.9V, an external supply is needed at the VCCpin. Enable inputs can be used to turn off the MOSFET and put the controller in a low current state. Status outputs indicate whether the MOSFETs are on or off.ApplicationsRedundant Power SuppliesSupply HoldupHigh Availability Systems and ServersTelecom and Network Infrastructure

The LTC4354 is a negative voltage diode-OR controller that drives two external N-channel MOSFETs. It replaces two Schottky diodes and the associated heatsink, saving power and area. The power dissipation is greatly reduced by using N-channel MOSFETs as the pass transistors. Power sources can easily be ORed together to increase total system power and reliability.When first powered up, the MOSFET body diode conducts the load current until the pass transistor is turned on. The LTC4354 servos the voltage drop across the pass transistors to ensure smooth transfer of current from one transistor to the other without oscillation.The MOSFETs are turned off in less than 1µs whenever the corresponding power source fails or is shorted. Fast turnoff prevents the reverse current from reaching a level that could damage the pass transistors.A fault detection circuit with an open drain output capable of driving an LED or opto-coupler indicates either MOSFET short, MOSFET open or supply failed.ApplicationsAdvancedTCA Systems–48V Distributed Power SystemsComputer Systems/ServersTelecom InfrastructureOptical Networks

The LTC4355 is a positive voltage ideal diode-OR controller that drives two external N-channel MOSFETs. Forming the diode-OR with N-channel MOSFETs instead of Schottky diodes reduces power consumption, heat dissipation and PC board area.With the LTC4355, power sources can easily be ORed together to increase total system reliability. The LTC4355 can diode-OR two positive supplies or the return paths of two negative supplies, such as in a –48V system.In the forward direction the LTC4355 controls the voltage drop across the MOSFET to ensure smooth current transfer from one path to the other without oscillation. If a power source fails or is shorted, fast turnoff minimizes reverse current transients.Power fault detection indicates if the input supplies are not in regulation, the inline fuses are blown, or the voltages across the MOSFETs are greater than the fault threshold.ApplicationsHigh Availability SystemsAdvancedTCA®(ATCA) Systems+48V and –48V Distributed Power SystemsTelecom Infrastructure

The LTC4357 is a positive high voltage ideal diode controller that drives an external N-channel MOSFET to replace a Schottky diode. When used in diode-OR and high current diode applications, the LTC4357 reduces power consumption, heat dissipation, voltage loss and PC board area.The LTC4357 easily ORs power sources to increase total system reliability. In diode-OR applications, the LTC4357 controls the forward voltage drop across the MOSFET to ensure smooth current transfer from one path to the other without oscillation. If the power source fails or is shorted, a fast turn-off minimizes reverse current transients.ApplicationsN + 1 Redundant Power SuppliesHigh Availability SystemsAdvancedTCA SystemsTelecom InfrastructureAutomotive Systems

The LTC4358 is a 5A ideal diode that uses an internal 20mΩ N-channel MOSFET to replace a Schottky diode when used in diode-OR and high current diode applications. The LTC4358 reduces power consumption, heat dissipation, and PC board area.The LTC4358 easily ORs power supplies together to increase total system reliability. In diode-OR applications, the LTC4358 regulates the forward voltage drop across the internal MOSFET to ensure smooth current transfer from one path to the other without oscillation. If the power source fails or is shorted, a fast turnoff minimizes reverse current transients.ApplicationsN+1 Redundant Power SuppliesHigh Availability SystemsTelecom InfrastructureAutomotive Systems

The LTC4359 is a positive high voltage ideal diode controller that drives an external N-channel MOSFET to replace a Schottky diode. It controls the forward-voltage drop across the 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. A shutdown mode is available to reduce the quiescent current to 9μA for load switch and 14µA for ideal diode applications.When used in high current diode applications, the LTC4359 reduces power consumption, heat dissipation, voltage loss and PC board area. With its wide operating voltage range, the ability to withstand reverse input voltage, and high temperature rating, the LTC4359 satisfies the demanding requirements of both automotive and telecom applications. The LTC4359 also easily ORs power sources in systems with redundant supplies.ApplicationsAutomotive Battery ProtectionRedundant Power SuppliesSupply HoldupTelecom InfrastructureComputer Systems/ServersSolar Systems

The LTC4360 overvoltage protection controller safeguards 2.5V to 5.5V systems from power supply overvoltage. It is designed for portable devices with multiple power supply options including wall adaptors, car battery adaptors and USB ports.The LTC4360 controls an external N-channel MOSFET in series with the input power supply. During overvoltage transients, the LTC4360 turns off the MOSFET within 1μs, isolating downstream components from the input supply. Inductive cable transients are absorbed by the MOSFET and load capacitance. In most applications, the LTC4360 provides protection from transients up to 80V without requiring transient voltage suppressors or other external components.The LTC4360 has a delayed start-up and an adjustable dV/dt ramp-up for inrush current limiting. APWRGDpin provides power good monitoring for VIN. Following an overvoltage condition, the LTC4360 automatically restarts with a start-up delay. The LTC4360-1 features a soft shutdown controlled by theONpin, while the LTC4360-2 controls an optional external P-channel MOSFET for negative voltage protection.ApplicationsUSB ProtectionHandheld ComputersCell/Smart PhonesMP3/MP4 PlayersDigital Cameras