The LT8609S is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator that consumes only 1.7?A of non-switching quiescent current. The LT8609S can deliver 2A of continuous current with peak loads of 3A (<1sec) to support applications such as GSM transceivers which require high transient loads. Top and bottom power switches are included with all necessary circuitry to minimize the need for external components. Low ripple Burst Mode operation enables high efficiency down to very low output currents while keeping the output ripple below 10mVP-P. A SYNC pin allows synchronization to an external clock, or spread spectrum modulation of switching frequencies for low EMI operation. Internal compensation with peak current mode topology allows the use of small inductors and results in fast transient response and good loop stability. The EN/UV pin has an accurate 1V threshold and can be used to program VIN undervoltage lockout or to shut down the LT8609S reducing the input supply current to 1?A. A capacitor on the TR/SS pin programs the output voltage ramp rate during start-up while the PG flag signals when VOUT is within ?8.5% of the programmed output voltage as well as fault conditions. The LT8609S is available in a small 16-lead 3mm ? 3mm LQFN package.APPLICATIONS General Purpose Step Down Low EMI Step Down

Demonstration circuit 2539A is an IEEE802.3bt (Draft 2.1) compliant Power over Ethernet (PoE) Powered Device (PD). It features the LT4295 PD interface and switching regulator controller and the LT4321 PoE ideal diode bridge controller.

The LTC4279 is an autonomous single port power sourcing equipment (PSE) controller designed for use in IEEE 802.3at Type 1, Type 2 and LTPoE++ compliant Power over Ethernet (PoE) systems. The LTC4279 provides fully autonomous IEEE 802.3 and LTPoE++ compliant operation without a microcontroller. The LTC4279 simplifies PSE implementation, requiring only a single supply and a small number of passive support components.The LTC4279 delivers lowest-in-industry heat dissipation by utilizing a low-RDS(ON) external MOSFET and a 0.1? sense resistor, eliminating the need for expensive heat sinks and increasing efficiency.PD discovery uses a proprietary dual-mode 4-point detection mechanism ensuring excellent immunity from false PD detection. Midspan PSEs are supported with physical layer classification and a 2.5 second backoff timer.Legacy and custom PDs are supported with pin-selectable LEGACY and UltraPWR modes. LEGACY mode detects and powers pre-IEEE specification PDs. UltraPWR mode aggressively turns on and powers custom PDs requiring high inrush and/or operational currents.Applications PoE PSE Endpoints (Switch/Router) PoE Midspan Power Injectors Power Forwarders Femto Cells Security Systems

The LT8672 is an active rectifier controller for reverse input protection. It drives an external N-channel MOSFET to replace a power Schottky diode. Its very low quiescent current and fast transient response meet the tough requirements in automotive applications where AC input signals of up to 100kHz are present. These signals are rectified with minimum power dissipation on the external FET, simplifying thermal management on the PCB.With a drop of only 20mV, the LT8672 solution eases the minimum input voltage requirement during cold crank and start-stop, allowing simpler and more efficient circuits. If the input power source fails or is shorted, a fast turn-off minimizes reverse current transients. An available shutdown mode reduces the quiescent current to 3.5?A.An integrated auxiliary boost regulator provides the required boost voltage to turn the external FET fully on. A power good pin signals when the external FET is ready to take load current.Applications Automotive Battery Protection Industrial Supplies Portable Instrumentation

The LT1997-3 combines a precision operational amplifier with highly-matched resistors to form a one-chip solution for accurately amplifying voltages. Gains from ?13 to +14 with accuracy of 0.006% (60ppm) can be achieved using no external components. The LT1997-3 is particularly well suited for use as a difference amplifier, where the excellent resistor matching results in a common mode rejection ratio of greater than 91dB.The amplifier features a 60?V maximum input offset voltage and a -3dB bandwidth of 1.1MHz (Gain = 1). The LT1997-3 operates from any supply voltage from 3.3V to 50V and draws only 350?A supply current. The output typically swings to within 100mV of either supply rail.The resistors maintain their excellent matching over temperature; the matching temperature coefficient is guaranteed less than 1ppm/?C. The resistors are extremely linear with voltage, resulting in a gain nonlinearity of less than 2ppm.The LT1997-3 is fully specified at 5V and ?15V supplies and from ?40?C to 125?C. The device is available in space saving 16-lead MSOP and 4mm ? 4mm DFN14 packages.Applications High Side or Low Side Current Sensing Bidirectional Wide Common Mode Range Current?Sensing High Voltage to Low Voltage Level Translation Industrial Data-Acquisition Front-Ends Replacement for Isolation Circuits Differential to Single-Ended Conversion

The LTC2992 is a rail-to-rail system monitor that measures current, voltage, and power of two supplies. It features an operating range of 2.7V to 100V and includes a shunt regulator for supplies above 100V. The voltage measurement range of 0V to 100V is independent of the input supply. Two ADCs simultaneously measure each supply?s current. A third ADC monitors the input voltages and four auxiliary external voltages. Each supply?s current and power is added for total system consumption. Minimum and maximum values are stored and an overrange alert with programmable thresholds minimizes the need for software polling. Data is reported via a standard I2C interface. Shutdown mode reduces current consumption to 25?A typically.The LTC2992 I2C interface includes separate data input and output pins for use with standard or opto-isolated I2C connections. The LTC2992-1 has an inverted data output for use with inverting opto-isolator configurations.Applications Telecom Infrastructure Industrial Equipment Automotive Computer Systems and Servers

Demonstration circuit 2594A is a step-down DC/DC converter and an inverting DC/DC converter with a 13V to 28V input voltage range, +12V at 4A, and –12V at up to 2.5A outputs featuring the LTM4655. The LTM4655 is a EN55022B compliant 40V, dual 4A or single 8A step-down or 50W inverting DC/DC μModule® Regulator. The switching frequencies of both channels are set at 1.2MHz on DC2594A. If the output voltage collapses sufficiently due to an overload or short-circuit condition, the internal oscillator will fold-back to one-fifth of the LTM4655’s programmed switching frequency, protecting the power switch from damage. The two channels can be paralleled for higher output current. See the data sheet for more information on setting up the board for paralleling the two outputs. The LTM4655 data sheet gives a complete description of the device, its operation and application information. The data sheet must be read in conjunction with the demo manual prior to working on or modifying DC2594A.

Demonstration circuit 2616A-C features a polyphase design using the LTM4645EY, a 25A high efficiency, switch mode step-down power µModule regulator. The input voltage range is from 6V to 15V. To use DC2616A-C for input voltage range from 4.7V to 6V, connect INTVCC to SVIN (change R22, R42, R55, R68 from OPT to 0Ω), DRVCC to VIN (change R21, R38, R52, R65 from 0Ω to OPT, R2, R39, R53, R66 from OPT to 0Ω). The output voltage range is 0.6V to 1.8V. The DC2616A-C can deliver a nominal 100A output current with four LTM4645 modules in parallel. As explained in the data sheet, output current derating is necessary for certain VIN, VOUT, and thermal conditions. The board operates in continuous conduction mode in heavy load conditions. For high efficiency at low load currents, the MODE_PLLIN jumper selects pulseskipping mode for noise sensitive applications or burst mode operation in less noise sensitive applications. The MODE_PLLIN pin also allows the LTM4645 to synchronize to an external clock signal. The phase shift between two adjacent phases is 90 degrees. DC2616A-C has the option of choosing both internal and external compensation circuit for LTM4645. The LTM4645 data sheet must be read in conjunction with this demo manual prior to working on or modifying demo circuit DC2616A-C.

The LTC6404 is a family of AC precision, very low noise, low distortion, fully differential input/output amplifiers optimized for 3V, single supply operation.The LTC6404-1 is unity-gain stable. The LTC6404-2 is designed for closed-loop gains greater than or equal to 2V/V. The LTC6404-4 is designed for closed-loop gains greater than or equal to 4V/V. The LTC6404 closed-loop bandwidth extends from DC to 600MHz. In addition to the normal un?ltered outputs (OUT+ and OUT?), the LTC6404 has a built-in 88.5MHz differential single-pole lowpass ?lter and an additional pair of ?ltered outputs (OUTF+, OUTF?). An input referred voltage noise of 1.5nV/?Hz make the LTC6404 able to drive state-of-the-art 16-/18-bit ADCs while operating on the same supply voltage, saving system cost and power. The LTC6404 is characterized, and maintains its performance for supplies as low as 2.7V and can operate on supplies up to 5.25V. It draws only 27.3mA, and has a hardware shutdown feature which reduces cur- rent consumption to 250?A.The LTC6404 family is available in a compact 3mm ? 3mm 16-pin leadless QFN package and operates over a ?40?C to 125?C temperature range.Applications Differential Input A/D Converter Driver Single-Ended to Differential Conversion/Amplification Common Mode Level Translation Low Voltage, Low Noise, Signal Processing

Demonstration circuit 2624A features the LT3094, an ultralow noise, ultrahigh power supply rejection ratio (PSRR) negative low dropout (LDO) regulator. DC2624A operates over an input range of –3.8V to –20V, and can deliver up to 500mA output current. It features ultralow noise (0.8µVRMS from 10Hz to 100kHz) and very high PSRR (75dB at 1MHz). The LT3094 enable function (EN/UVLO pin) is bidirectional and can be controlled with either a positive or a negative voltage. The LT3094 also offers programmable current limit functionality by connecting a resistor from ILIM to GND. Current monitoring is also achieved by sensing the ILIM pin voltage. The VIOC tracking function controls an upstream switching converter to maintain a constant voltage across the regulator and, hence, minimize power dissipation. The power good feedback (PGFB) pin is used to set a programmable power good threshold, and activates the fast start-up circuitry. To use the power good function, connect an external voltage source at VEXT. If power good and fast start-up functionality are not needed, tie PGFB to IN. Built-in protection includes reverse battery protection, reverse current protection, internal current limit with foldback, and thermal limit with hysteresis. The LT3094 data sheet gives a complete description of the part, operation and applications information. The data sheet must be read in conjunction with this demo manual for demonstration circuit DC2624A. The LT3094 is assembled in 12-lead MSOP and 3mm × 3mm DFN packages with an exposed pad on the bottom-side of the IC. Proper board layout is essential for maximum thermal performance.