The LTC4227 offers ideal diode-OR and Hot Swap? functions for two power rails by controlling external Nchannel MOSFETs. MOSFETs acting as ideal diodes replace two high power Schottky diodes and the associated heat sinks, saving power and board area. A Hot Swap control MOSFET allows a board to be safely inserted and removed from a live backplane by limiting inrush current. The supply output is also protected against short-circuit faults with a fast acting current limit and internal timed circuit breaker.The LTC4227 regulates the forward voltage drop across the MOSFETs to ensure smooth current transfer from one supply to the other without oscillation. The ideal diodes turn on quickly to reduce the load voltage droop during supply switchover. If the input supply fails or is shorted, a fast turn-off minimizes reverse-current transients.The LTC4227 allows turn-on/off control, and reports fault and power good status for the supply. Part Overcurrent Fault Start-Up Delay LTC4227-1 Latch Off 100ms LTC4227-2 Retry 100ms LTC4227-3 Latch Off 1.6ms LTC4227-4 Retry 1.6ms Applications Redundant Power Supplies and Supply Holdup Computer Systems and Servers Telecom Networks

Demonstration circuit 1626A is a dual output 1.5V/15A and 1.2V/15A synchronous buck converter operating with a switching frequency of 300kHz over an input voltage range of 4.5V to 26V. The demo board comes in two versions. The -A version uses inductor DCR current sensing with an iron powder inductor for high efficiency. The -B version uses a 2.5mΩ sense resistor for accurate current sensing with a low DCR ferrite inductor.

The LTC3838 is a dual, PolyPhase? synchronous step-down DC/DC switching regulator controller. Two independent channels drive all N-channel power MOSFETs. The controlled on-time, valley current mode control architecture allows for fast transient response and constant frequency switching in steady-state operation, independent of VIN, VOUT and load current. Its load-release transient detection feature significantly reduces overshoot at low output voltages.Differential output voltage sensing, along with a precision internal reference, offers an accurate ?0.67% output regulation on Channel 1, even if the remote output ground deviates from local ground by ?500mV. The second channel can either provide an independent ?1% output, or together with the first channel of this controller, serve as one of the PolyPhase channels for a single-output voltage.The switching frequency can be programmed from 200kHz to 2MHz with an external resistor, and can be synchronized to an external clock. Very low tON and tOFF times allow for near 0% and near 100% duty cycles, respectively. Voltage tracking soft start-up and multiple safety features are provided.See below for a comparison of LTC3838, LTC3838-1 and LTC3838-2. Part Number Description LTC3838 ? ?0.67% Differential Output Voltage Accuracy Over Temperature on Channel 1, ?1% Output Regulation on Channel 2, Separate Per Channel 30mV to 100mV Current Sense Range Controls LTC3838-1 ? ?0.67% Differential Output Voltage Accuracy Over Temperature on Both Channel 1 and Channel 2, Single Pin 30mV/60mV Current Sense Range Controls LTC3838-2 ?0.67% Differential Output Voltage Accuracy With Internal Reference on Channel 1, ?4mV Differential with External Reference Voltage on Channel 2, Fixed 30mV Current Sense Range Applications Distributed Power Systems Point-of-Load Converters Computing Systems Data Communication Systems

The ADM1063 is a configurable supervisory/sequencing device that offers a single-chip solution for supply monitoring and sequencing in multiple supply systems. In addition to these functions, the ADM1063 integrates a 12-bit ADC that can be used to accurately read back up to 12 separate voltages.The device also provides up to 10 programmable inputs for monitoring under, over, or out-of-window faults on up to 10 supplies. In addition, 10 programmable outputs can be used as logic enables. Six of these programmable outputs can provide up to a 12 V output for driving the gate of an n-FET that can be placed in the path of a supply.ApplicationsCentral office systems Servers/routers Multivoltage system line cards DSP/FPGA supply sequencing In-circuit testing of margined supplies

The ADM1066 Super Sequencer? is a configurable supervisory/ sequencing device that offers a single-chip solution for supply monitoring and sequencing in multiple-supply systems. In addition to these functions, the ADM1066 integrates a 12-bit ADC and six 8-bit voltage output DACs. These circuits can be used to implement a closed-loop margining system that enables supply adjustment by altering either the feedback node or reference of a dc-to-dc converter using the DAC outputs. Supply margining can be performed with a minimum of external components. The margining loop can be used for in-circuit testing of a board during production (for example, to verify board functionality at ?5% of nominal supplies), or it can be used dynamically to accurately control the output voltage of a dc-to-dc converter.APPLICATIONS Central office systems Servers/routers Multivoltage system line cards DSP/FPGA supply sequencing In-circuit testing of margined supplies

The ADM1169 Super Sequencer? is a configurable supervisory/ sequencing device that offers a single-chip solution for supply monitoring and sequencing in multiple supply systems. In addition to these functions, the ADM1169 integrates a 12-bit ADC and four 8-bit voltage output DACs. These circuits can be used to implement a closed-loop margining system that enables supply adjustment by altering either the feedback node or reference of a dc-to-dc converter using the DAC outputs. Supply margining can be performed with a minimum of external components. The margining loop can be used for in-circuit testing of a board during production (for example, to verify board functionality at ?5% of nominal supplies), or it can be used dynamically to accurately control the output voltage of a dc-to-dc converter. The device also provides up to eight programmable inputs for monitoring undervoltage faults, overvoltage faults, or out-of-window faults on up to eight supplies. In addition, there are eight programmable outputs that can be used as logic enables. Six of these programmable outputs can also provide up to a 12 V output for driving the gate of an N-FET that can be placed in the path of a supply. The logical core of the device is a sequencing engine (SE). This state machine-based construction provides up to 63 different states. This design enables very flexible sequencing of the outputs, based on the condition of the inputs. A block of nonvolatile EEPROM is available that can be used to store user-defined information and may also be used to hold a number of fault records that are written by the sequencing engine defined by the user when a particular fault or sequence occurs. The ADM1169 is controlled via configuration data that can be programmed into an EEPROM. The entire configuration can be programmed using an intuitive GUI-based software package provided by Analog Devices, Inc.

The ADM1170 is a Hot Swap controller that allows a board to be safely inserted and removed from a live backplane. This is achieved using a pass FET with a current control loop that monitors the input current using a sense resistor. An internal charge pump is used to enhance the gate of theexternal high side N-channel FET. When an over current condition is detected the gate voltage of the FET is reduced to limit the current flowing through the sense resistor. The ADM1170 operates with a supply voltage ranging from 2.7V to 16.5V. Using separate SENSE pins from VCC the ADM1170 allows for the hot swap of supplies ranging down to 1.6V. During an overcurrent condition the timer cap determines the amount of time the FET will remain in this condition. The ON (ON-CLR) pin is the enable input for the device and also acts as a latched fault reset for the ADM1170-2 model. The SS pin is used to control the inrush current profile by ramping up the current sense limit at a rate set by the SS capacitor. This device is available in two options: the ADM1170-1 will automatic retry for over-current fault and the ADM1170-2 will latch-off for an over-current fault. The ADM1170 is packaged in an 8-lead TSOT packageAPPLICATIONS Hot Swap Board Insertion ? Line Cards, Raid Systems Electronic Circuit Breaker Industrial High Side Switch/Circuit Breaker

The ADM1171 is a Hot Swap controller that allows a board to be safely inserted and removed from a live backplane. This is achieved using a pass FET with a current control loop that monitors the input current using a sense resistor. An internal charge pump is used to enhance the gate of theexternal high side N-channel FET. When an over current condition is detected the gate voltage of the FET is reduced to limit the current flowing through the sense resistor. The ADM1171 operates with a supply voltage ranging from 2.7V to 16.5V. During an overcurrent condition the timer capdetermines the amount of time the FET will remain in this condition. The ON (ON/CLR) pin is the enable input for the device and also acts as a latched fault reset for the ADM1171-2 model. The magnitude of the current flowing through the Sense resistor can be determined by the voltage on the CSOUT pin The SS pin allows the user to control the soft start profile of the current ramp at start-up via an external capacitor. This device is available in two options: the ADM1171-1 will automatic retry for over-current fault and the ADM1171-2 will latch-off for an over-current fault. The ADM1171 is packaged in an 8-lead TSOT package.APPLICATIONS Hot Swap Board Insertion ? Line Cards, Raid systems Electronic Circuit Breaker Industrial High Side Switch/Circuit Breaker

The ADM1178 is an integrated hot swap controller and current sense amplifier that offers digital current and voltage monitoring via an on-chip 12-bit analog-to-digital converter (ADC), communicated through an I2C? interface.An internal current sense amplifier measures voltage across the sense resistor in the power path via the VCC pin and the SENSE pin.The ADM1178 limits the current through this resistor by control-ling the gate voltage (via the GATE pin) of an external N-channel FET in the power path. The voltage across the sense resistor (and therefore the inrush current) is kept below a preset maximum.The ADM1178 protects the external FET by limiting the time that the maximum current runs through it. This current limit period is set by the value of the capacitor attached to the TIMER pin. Additionally, the device provides protection from overcurrent events that may occur after the hot swap event is complete. In case of a short-circuit event, the current in the sense resistor exceeds an overcurrent trip threshold, and the FET is switched off immediately by pulling down the GATE pin.A 12-bit ADC can measure the current seen in the sense resistor, as well as the supply voltage on the VCC pin. An alert output can be set to trigger when the ADC current reading exceeds a programmed overcurrent limit threshold.An industry-standard I2C interface allows a controller to read current and voltage data from the ADC. Measurements can be initiated by an I2C command. Alternatively, the ADC can run continuously, and the user can read the latest conversion data whenever it is required. Up to four unique I2C addresses can be created, depending on how the ADR pin is connected.The ADM1178 is packaged in a 10-lead MSOP.ApplicationsPower monitoring/power budgeting Central office equipment Telecommunication and data communication equipment PCs/servers

The ADM1184 is an integrated, 4-channel voltage-monitoring device. A 2.7 V to 5.5 V power supply is required on the VCC pin to power the device.Four precision comparators monitor four voltage rails. Each comparator has a 0.6 V reference with a worst-case accuracy of 0.8%. Resistor networks that are external to the VIN1, VIN2, VIN3, and VIN4 pins set the trip points for the monitored supply rails.The ADM1184 has four open-drain outputs. Of these outputs, OUT1 to OUT3 can be used to enable power supplies, and PWRGD is a common power-good output indicating that all monitored supplies are above their respective thresholds.OUT1 to OUT3 are dependent on their associated VINx input (that is, VIN1, VIN2, or VIN3). If a supply monitored by VINx drops below its programmed threshold, the associated OUTx pin and PWRGD are disabled.PWRGD is a common power-good output indicating the status of all monitored supplies. There is an internal 190 ms (typical) delay associated with the assertion of the PWRGD output. If VIN1, VIN2, VIN3, or VIN4 drops below its programmed threshold, PWRGD is deasserted immediately.The ADM1184 is available in a 10-lead mini small outline package (MSOP).APPLICATIONS Monitor and alarm functions Telecommunications Microprocessor systems PC/servers