Analog Devices

The LTC1609 is a 200ksps, serial sampling 16-bit A/D converter that draws only 65mW (typical) from a single 5V supply. This easy-to-use device includes a sample-and- hold, a precision reference, a switched capacitor successive approximation A/D and trimmed internal clock.The input range is specified for bipolar inputs of ±10V, ±5V and ±3.3V and unipolar inputs of 0V to 10V, 0V to 5V and 0V to 4V. Maximum DC specs include ±2LSB INL and 16-bit no missing codes overtemperature. It has a typical signal-to-noise ratio of 87dB.The ADC has a high speed serial interface. The serial output data can be clocked out using either the internal serial shift clock or be clocked out by an external shift clock. A separate convert start input(R/C) and a data ready signal (BUSY) ease connections to FIFOs, DSPs and microprocessors.ApplicationsIndustrial Process ControlMultiplexed Data Acquisition SystemsHigh Speed Data Acquisition for PCsDigital Signal Processing

The LTC1623 SMBus switch controller is a slave device that controls two high-side N-channel MOSFETs on either the SMBus or the I2C bus. The LTC1623 operates with an input voltage from 2.7V to 5.5V with a low standby current of 14µA (at 3.3V). In accordance with the SMBus specification, the LTC1623 maintains the 0.6V VILand 1.4V VIHinput thresholds throughout the supply voltage range.Using the 2-wire interface, CLK and DATA, the LTC1623 monitors the bus for a start condition (DATA going from high to low while CLK is high). Once detected, the LTC1623 compares its address with the first (address) byte sent over the bus from the master. If matched, the LTC1623 will execute the second (command) byte from the master and independently control the built-in charge pumps to drive two external switches.The LTC1623 has two three-state programmable address pins, thus allowing eight different addresses and a total of sixteen available switches on the same bus.ApplicationsComputer Peripheral ControlLaptop Computer Power Plane SwitchingPortable Equipment Power ControlIndustrial Control SystemsHandheld Equipment

The LTC1625 is a synchronous step-down switching regulator controller that drives external N-Channel power MOSFETs using few external components. Current mode control with MOSFET VDSsensing eliminates the need for a sense resistor and improves efficiency. The frequency of a nominal 150kHz internal oscillator can be synchronized to an external clock over a 1.5:1 frequency range.Burst Mode™operation at low load currents reduces switching losses and low dropout operation extends operating time in battery-powered systems. A forced continuous mode control pin can assist secondary winding regulation by disabling Burst Mode operation when the main output is lightly loaded.Fault protection is provided by foldback current limiting and an output overvoltage comparator. An external capacitor attached to the RUN/SS pin provides soft start capability for supply sequencing. A wide supply range allows operation from 3.7V (3.9V for LTC1625I) to 36V at the input and 1.19V to VINat the output.ApplicationsNotebook and Palmtop Computers, PDAsCellular Telephones and Wireless ModemsBattery ChargersDistributed Power

The LTC1627 is a monolithic current mode synchronous buck regulator using a fixed frequency architecture. The operating supply range is from 8.5V down to 2.65V, making it suitable for one or two lithium-ion battery-powered applications. Burst Mode operation provides high efficiency at low load currents. 100% duty cycle provides low dropout operation, which extends operating time in battery-operated systems.The operating frequency is internally set at 350kHz, allowing the use of small surface mount inductors. For switching noise sensitive applications it can be externally synchronized up to 525kHz. The SYNC/FCB control pin guarantees regulation of secondary windings regardless of load on the main output by forcing continuous operation. Burst Mode operation is inhibited during synchronization or when the SYNC/FCB pin is pulled low to reduce noise and RF interference. Soft-start is provided by an external capacitor.Optional bootstrapping enhances the internal switch drive for single lithium-ion cell applications. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode, saving components and board space. The LTC1627 comes in an 8-lead SO package.ApplicationsCellular TelephonesPortable InstrumentsWireless ModemsRF CommunicationsDistributed Power SystemsScannersSingle and Dual Cell Lithium

The LTC1628/LTC1628-PG are high performance dual step-down switching regulator controllers that drive all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows adjustment of the frequency up to 300kHz. Power loss and noise due to the ESR of the input capacitors are minimized by operating the two controller output stages out of phase.OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The precision 0.8V reference and power good output indicator are compatible with future microprocessor generations, and a wide 3.5V to 30V (36V maximum) input supply range encompasses all battery chemistries.A RUN/SS pin for each controller provides both soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when overcurrent latchoff is disabled. Output overvoltage protection circuitry latches on the bottom MOSFET until VOUTreturns to normal. The FCB mode pin can select among Burst Mode, constant frequency mode and continuous inductor current mode or regulate a secondary winding. The LTC1628-PG includes a power good output pin that replaces the FLTCPL, fault coupling control pin of the LTC1628.ApplicationsNotebook and Palmtop Computers, PDAsBattery ChargersPortable InstrumentsBattery-Operated Digital DevicesDC Power Distribution Systems

The LTC1629/LTC1629-PG are multiple phase, dual, synchronous step-down current mode switching regulator controllers that drive N-channel external power MOSFET stages in a phase-lockable fixed frequency architecture. The PolyPhase™controller drives its two output stages out of phase at frequencies up to 300kHz to minimize the RMS ripple currents in both input and output capacitors. The output clock signal allows expansion for up to 12 evenly phased controllers for systems requiring 15A to 200A of output current. The multiple phase technique effectively multiplies the fundamental frequency by the number of channels used, improving transient response while operating each channel at an optimum frequency for efficiency. Thermal design is also simplified.An internal differential amplifier provides true remote sensing of the regulated supply’s positive and negative output terminals as required for high current applications.A RUN/SS pin provides both soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when the overcurrent latch-off is disabled. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC1629-PG includes a power good output pin that replaces the AMPMD control pin of the LTC1629.ApplicationsDesktop ComputersInternet ServersLarge Memory ArraysDC Power Distribution Systems

The LTC1642A is a 16-pin Hot Swap™ controller that allows a board to be safely inserted and removed from a live backplane. Using an external N-Channel pass transistor, the board supply voltage can be ramped up at an adjustable rate. A high side switch driver controls the N-Channel gate for supply voltages ranging from 2.97V to 16.5V.The SENSE pin allows foldback limiting of the load current, with circuit breaker action after an adjustable delay time. The delay allows the part to power-up in current limit. The CRWBR output can be used to trigger an SCR for crowbar protection of the load if the input supply exceeds an adjustable threshold. TheRESEToutput can generate a system reset with adjustable delay when the supply voltage falls below an adjustable threshold. The ON pin cycles the board power. The LTC1642A is available in the 16-pin SSOP package.NotesLTC1642LTC1642ARecommended for application where VCCis Higher than 12VApplicationsHot Board InsertionElectronic Circuit BreakerInfiniBand™Systems

The LTC1643A is a Hot Swap™controller that allows a board to be safely inserted and removed from a live PCI-Bus slot. Two external N-channel transistors control the 3.3V and 5V supplies while on-chip switches control the –12V and 12V supplies. All supply voltages can be ramped up at a programmable rate. An electronic circuit breaker protects all four supplies against overcurrent faults. The foldback current limit feature limits current spikes and power dissipation when shorts occur and allows boards with large capacitances to be powered up without tripping the circuit breaker. ThePWRGDoutput indicates when all of the supply voltages are within tolerance and theFAULToutput indicates an overcurrent condition. The ON(LTC1643AH)/ON(LTC1643AL/ LTC1643AL-1) pin is used to cycle the board power or reset the circuit breaker. The LTC1643AL-1 has the ±12V power good comparators disabled.The LTC1643A is available in a 16-pin narrow SSOP package.ApplicationsPCI-Based ServersCompactPCI Compliant Boards

The LTC1644 is a Hot Swap™controller that allows a board to be safely inserted and removed from a CompactPCI bus slot. External N-channel transistors control the 3.3V/5V supplies, while on-chip switches control the –12V and 12V supplies. The 3.3V and 5V supplies can be ramped up at a programmable rate. Electronic circuit breakers protect all four supplies against overcurrent faults. ThePWRGDoutput indicates when all of the supply voltages are within tolerance. The OFF/ONpin is used to cycle the board power or reset the circuit breaker. The PRECHARGE output can be used to bias the bus I/O pins during card insertion and extraction. PCI_RST# is combined on-chip with HEALTHY# in order to generate LOCAL_PCI_RST#.ApplicationsHot Board Insertion into CompactPCI Bus

The LTC1645 is a 2-channel Hot Swap™controller that allows a board to be safely inserted and removed from a live backplane. Using external N-channel pass transistors, the supply voltages can be ramped at a programmable rate. Two high side switch drivers control the N-channel gates for supply voltages ranging from 1.2V to 12V. The two channels can be set to ramp up and down separately, or they can be programmed to rise and fall simultaneously, ensuring power supply tracking at the two outputs.Programmable electronic circuit breakers protect against shorts at either output. TheRESEToutput can be used to generate a system reset when a supply voltage falls below a user-programmed voltage. An additional spare comparator is available for monitoring a second supply voltage.The LTC1645 is available in the 8- and 14-pin SO packages.ApplicationsHot Board InsertionPower Supply SequencingElectronic Circuit Breaker