Analog Devices Inc./Maxim Integrated

The MAX5954 hot-plug controller is designed for PCI Express® applications. The device provides hot-plug control for 12V, 3.3V, and 3.3V auxiliary supplies of a single PCI Express (PCI-E) slot. The MAX5954's logic inputs/outputs allow interfacing directly with the system hot-plug management controller or through an SMBus™ with an external I/O expander. Integrated debounced attention switch and present-detect signals are included to simplify system design.The MAX5954 drives two external n-channel MOSFETs to control the 12V and 3.3V main outputs. The 3.3V auxiliary output is controlled through an internal 0.3Ω n-channel MOSFET. An internal charge pump provides gate drive for the 12V output while the gate drive of the 3.3V output is driven by the 12V input supply. The 3.3V auxiliary output is completely independent from the main outputs with its own charge pump.At power-up, the MAX5954 keeps all of the external MOSFETs off until the supplies rise above their respective undervoltage lockout (UVLO) thresholds. The device keeps the internal MOSFET off only until the auxiliary input supply rises above its UVLO threshold. Upon a turn-on command, the MAX5954 enhances the external and internal MOSFETs slowly with a constant gate current to limit the power-supply inrush current. The MAX5954 actively limits the current of all outputs at all times and shuts down if an overcurrent condition persists for longer than a programmable overcurrent timeout. Thermal-protection circuitry also shuts down all outputs if the die temperature exceeds +150°C. After an overcurrent or overtemperature fault condition, the MAX5954L latches off while the MAX5954A automatically restarts after a restart time delay. The device is available in a 36-pin (6mm x 6mm) thin QFN package and operates over the -40°C to +85°C temperature range.ApplicationsDesktop/Mobile Server PlatformsEmbedded DevicesServersWorkstations

The MAX5955 and MAX5956 are +1V to +13.2V dual hot-swap controllers with independent on/off control for complete protection of dual-supply systems. They allow the safe insertion and removal of circuit cards into live backplanes. The MAX5955 and MAX5956 operate down to 1V provided one of the inputs is above 2.7V.The discharged filter capacitors of the circuit card provide low impedance to the live backplane. High inrush currents from the backplane to the circuit card can burn up connectors and components, or momentarily collapse the backplane power supply leading to a system reset. The MAX5955 and MAX5956 hot-swap controllers prevent such problems by gradually ramping up the output voltage and regulating the current to a preset limit when the board is plugged in, allowing the system to stabilize safely. After the startup cycle is completed, two on-chip comparators provide VariableSpeed/BiLevel™ protection against short-circuit and overcurrent faults, as well as immunity against system noise and load transients. In the event of a fault condition, the load is disconnected. The MAX5955B and MAX5956B must be unlatched after a fault, and the MAX5955A and MAX5956A automatically restart after a fault.The MAX5955 and MAX5956 integrate an on-board charge pump to drive the gates of low-cost, external n-channel MOSFETs. The devices offer integrated features like startup current regulation and current glitch protection to eliminate external timing resistors and capacitors. These devices provide open-drain status outputs, an adjustable startup timer, and adjustable current limits. The MAX5955 provides output undervoltage/ overvoltage protection for each channel, while the MAX5956 provides undervoltage/overvoltage monitoring for each channel.The MAX5955 and MAX5956 are available in a space-saving 16-pin QSOP package.ApplicationsBase Station Line CardsHot Plug-In Daughter CardsNetwork Switches, Routers, HubsPortable Computer Device Bays (Docking Stations)Power-Supply SequencingRAIDSolid-State Circuit Breakers

The MAX5961 0 to 16V, quad, hot-swap controller provides complete protection for systems with up to four distinct supply voltages. The device allows the safe insertion and removal of circuit cards into live backplanes. The MAX5961 is an advanced hot-swap controller that monitors voltage and current with an internal 10-bit ADC. The device provides two levels of overcurrent circuit-breaker protection; a fast-trip threshold for a fast turn-off, and a lower slow-trip threshold for a delayed turn-off. The maximum overcurrent circuit-breaker threshold range is set independently for each channel with a trilevel input (ILIM_) or by programming though an I²C interface.The internal 10-bit ADC is multiplexed to monitor the output voltage and current of each hot-swap channel. The total time to cycle through all the eight measurements is 100µs (typ). Each 10-bit value is stored in an internal circular buffer so that 50 past samples of each signal can be read back through the I²C interface at any time or after a fault condition.The MAX5961 can be configured as four independent hot-swap controllers, hot-swap controllers operating in pairs, or as a group of four hot-swap controllers.The device also includes five digital comparators per hot-swap channel to implement overcurrent warning, two levels of overvoltage detection, and two levels of undervoltage detection. The limits for overcurrent, overvoltage, and undervoltage are user-programmable. When any of the measured values violates the programmable limits, an external active-low ALERT signal is asserted. In addition to the active-low ALERT signal, depending on the selected operating mode, the MAX5961 can deassert a power-good signal and/or turn-off the external MOSFET.The MAX5961 is available in a 48-pin thin QFN package and operates over the -40°C to +85°C extended temperature range.ApplicationsASICsDisk DrivesPCI Express® Hot PlugServersStorage Systems

The MAX5965A/MAX5965B are quad, monolithic, -48V power controllers designed for use in IEEE® 802.3af-compliant/IEEE 802.3at-compatible power-sourcing equipment (PSE). These devices provide powered device (PD) discovery, classification, current limit, DC and AC load disconnect detections in compliance with the IEEE 802.3af standard. The MAX5965A/MAX5965B are pin compatible with the MAX5952/MAX5945/LTC4258/LTC4259A PSE controllers and provide additional features.The MAX5965A/MAX5965B feature a high-power mode that provides up to 45W per port. The MAX5965A/ MAX5965B provide new Class 5 and 2-event classification (Class 6) for detection and classification of high-power PDs. The MAX5965A/MAX5965B provide instantaneous readout of each port current through the I²C interface. The MAX5965A/MAX5965B also provide high-capacitance detection for legacy PDs.These devices feature an I²C-compatible, 3-wire serial interface, and are fully software configurable and programmable. The class-overcurrent detection function enables system power management to detect if a PD draws more than the allowable current. The MAX5965A/MAX5965B's extensive programmability enhances system flexibility, enables field diagnosis, and allows for uses in other applications.The MAX5965A/MAX5965B provide four operating modes to suit different system requirements. Auto mode allows the devices to operate automatically without any software supervision. Semi-automatic mode automatically detects and classifies a device connected to a port after initial software activation, but does not power up that port until instructed to by software. Manual mode allows total software control of the device and is useful for system diagnostics. Shutdown mode terminates all activities and securely turns off power to the ports.The MAX5965A/MAX5965B provide input undervoltage lockout (UVLO), input undervoltage detection, a load-stability safety check during detection, input overvoltage lockout, overtemperature detection, output voltage slew-rate limit during startup, power-good status, and fault status. The MAX5965A/MAX5965B's programmability includes startup timeout, overcurrent timeout, and load-disconnect detection timeout.The MAX5965A/MAX5965B are available in a 36-pin SSOP package and are rated for both extended (-40°C to +85°C) and upper commercial (0°C to +85°C) temperature ranges.ApplicationsMidspan Power InjectorsPower-Sourcing Equipment (PSE)Switches/Routers

The MAX5969A/MAX5969B provide a complete interface for a powered device (PD) to comply with the IEEE® 802.3af/at standard in a power-over-Ethernet (PoE) system. The MAX5969A/MAX5969B provide the PD with a detection signature, classification signature, and an integrated isolation power switch with inrush current control. During the inrush period, the MAX5969A/MAX5969B limit the current to less than 180mA before switching to the higher current limit (720mA to 880mA) when the isolation power MOSFET is fully enhanced. The devices feature an input UVLO with wide hysteresis and long deglitch time to compensate for twisted-pair cable resistive drop and to assure glitch-free transition during power-on/-off conditions. The MAX5969A/MAX5969B can withstand up to 100V at the input.The MAX5969A/MAX5969B support a 2-event classification method as specified in the IEEE 802.3at standard and provide a signal to indicate when probed by Type 2 power-sourcing equipment (PSE). The devices detect the presence of a wall adapter power-source connection and allow a smooth switchover from the PoE power source to the wall power adapter.The MAX5969A/MAX5969B also provide a power-good (PG) signal, two-step current limit and foldback, overtemperature protection, and di/dt limit.The MAX5969A/MAX5969B are available in a space-saving, 10-pin, 3mm × 3mm, TDFN power package. These devices are rated over the -40°C to +85°C extended temperature range.ApplicationsIEEE 802.3af/at Powered DevicesIP Phones, Wireless Access Nodes, IP Security CamerasWiMAX™ Base Station

The MAX5969A/MAX5969B provide a complete interface for a powered device (PD) to comply with the IEEE® 802.3af/at standard in a power-over-Ethernet (PoE) system. The MAX5969A/MAX5969B provide the PD with a detection signature, classification signature, and an integrated isolation power switch with inrush current control. During the inrush period, the MAX5969A/MAX5969B limit the current to less than 180mA before switching to the higher current limit (720mA to 880mA) when the isolation power MOSFET is fully enhanced. The devices feature an input UVLO with wide hysteresis and long deglitch time to compensate for twisted-pair cable resistive drop and to assure glitch-free transition during power-on/-off conditions. The MAX5969A/MAX5969B can withstand up to 100V at the input.The MAX5969A/MAX5969B support a 2-event classification method as specified in the IEEE 802.3at standard and provide a signal to indicate when probed by Type 2 power-sourcing equipment (PSE). The devices detect the presence of a wall adapter power-source connection and allow a smooth switchover from the PoE power source to the wall power adapter.The MAX5969A/MAX5969B also provide a power-good (PG) signal, two-step current limit and foldback, overtemperature protection, and di/dt limit.The MAX5969A/MAX5969B are available in a space-saving, 10-pin, 3mm × 3mm, TDFN power package. These devices are rated over the -40°C to +85°C extended temperature range.ApplicationsIEEE 802.3af/at Powered DevicesIP Phones, Wireless Access Nodes, IP Security CamerasWiMAX™ Base Station