The LM4050/LM4051 are precision two-terminal, shuntmode, bandgap voltage references available in fixed reverse breakdown voltages of 1.225V, 2.048V, 2.500V, 3.000V, 3.3V, 4.096V, and 5.000V. Ideal for space-critical applications, the LM4050/LM4051 are offered in the subminiature 3-pin SC70 surface-mount packages (1.8mm x 1.8mm), 50% smaller than comparable devices in SOT23 surface-mount package (SOT23 versions are also available).Laser-trimmed resistors ensure excellent initial accuracy. With a 50ppm/°C temperature coefficient, these devices are offered in three grades of initial accuracy ranging from 0.1% to 0.5%. The LM4050/LM4051 have a 60µA to 15mA shunt-current capability with low dynamic impedance, ensuring stable reverse breakdown voltage accuracy over a wide range of operating temperatures and currents. The LM4050/LM4051 do not require an external stabilizing capacitor while ensuring stability with any capacitive loads.The LM4050/LM4051 specifications are guaranteed over the temperature range of -40°C to +125°C.ApplicationsAutomotiveCell PhonesIndustrial Process ControlsNotebook ComputersPortable Battery-Powered Equipment

The LT1766/LT1766-5 are 200kHz monolithic buck switching regulators that accept input voltages up to 60V. A high efficiency 1.5A, 0.2Ω switch is included on the die along with all the necessary oscillator, control and logic circuitry. A current mode control architecture delivers fast transient response and excellent loop stability.Special design techniques and a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch. Patented circuitry maintains peak switch current over the full duty cycle range. A shutdown pin reduces supply current to 25μA and the device can be externally synchronized from 228kHz to 700kHz with logic-level inputs.The LT1766/LT1766-5 are available in a 16-pin fused-lead SSOP package or a TSSOP package with exposed backside for improved thermal performance.Applications High Voltage, Industrial and Automotive Portable Computers Battery-Powered Systems Battery Chargers Distributed Power Systems

The LTC3700 is a constant frequency current mode stepdown (buck) DC/DC controller with excellent AC and DC load and line regulation. The on-chip 150mA low dropout (LDO) linear regulator can be powered from the buck controller’s input supply, its own independent input supply or the buck regulator’s output. The buck controller incorporates an undervoltage lockout feature that shuts down the controller when the input voltage falls below 2.1V.The buck regulator provides a ±2.5% output voltage accuracy. It consumes only 210µA of quiescent current in normal operation with the LDO consuming an additional 50µA. In shutdown, a mere 10µA (combined) is consumed.For applications where efficiency is a prime consideration, the buck controller is configured for Burst Mode operation which enhances efficiency at low output current. To further maximize the life of a battery source, the external P-channel MOSFET is turned on continuously in dropout (100% duty cycle). High constant operating frequency of 550kHz allows the use of a small external inductor.The LDO is protected by both current limit and thermal shutdown circuits.The LTC3700 is available in a tiny 10-pin MSOP.Applications Notebook Computers Portable Instruments One or Two Li-Ion Battery-Powered Applications

The LTC3707-SYNC is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows phase-lockable frequency of 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 4.5V to 28V (30V 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 VOUT returns 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 IC includes a power good output pin that indicates when both outputs are within 7.5% of their designed set point. External Synchronization LTC3707 No LTC3707-SYNC Yes Applications Notebook and Palmtop Computers, PDAs Telecom Systems Portable Instruments Battery-Operated Digital Devices DC Power Distribution Systems

The LTC3720 is a synchronous step-down switching regulator controller for CPU power. An output voltage between 1.05V and 1.825V is selected by a 5-bit code (Intel VRM8.5 VID specification). The controller uses a valley current control architecture to deliver very low duty cycles without requiring a sense resistor. Operating frequency is selected by an external resistor and is compensated for variations in VIN and VOUT.Discontinuous mode operation provides high efficiency operation at light loads. A forced continuous control pin reduces noise and RF interference and can assist secondary winding regulation by disabling discontinuous mode operation when the main output is lightly loaded.Fault protection is provided by internal foldback current limiting, an output overvoltage comparator and optional short-circuit shutdown timer. Soft-start capability for supply sequencing is accomplished using an external timing capacitor. The regulator current limit level is also user programmable. Wide supply range allows operation from 4V to 36V at the input.Applications Power Supplies for Pentium® Processors Notebook Computers and Servers

The LTC3727A-1 is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows phase-lockable frequency of up to 550kHz. Power loss and noise due to the ESR of the input capacitors are minimized by operating the two controller output stages out of phase.The LTC3727A-1 is an improved version of the LTC3727 family of parts. It has smaller output ripple while in the drop-out condition and shorter minimum on-time.OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. There is a precision 0.8V reference and a power good output indicator. A wide 4V to 30V (36V maximum) input supply range encompasses all battery chemistries.A RUN/SS pin for each controller provides soft-start. Current foldback limits MOSFET heat dissipation during short-circuit conditions. Output overvoltage protection circuitry protects the controller until VOUT returns to normal. VIN Range VREF Accuracy Over Temp Latch-Off Min On-Time LTC3727 4V - 36V ±1% No 180ns LTC3727-1 4V - 36V ±1% Yes 180ns LTC3727A-1 4V - 36V ±1% No 120ns LTC3727LX-1 4V - 32V ±1.5% No 120ns Applications Telecom Systems Automotive Systems Battery-Operated Digital Devices

The LTC3727/LTC3727-1 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 phase-lockable frequency of up to 550kHz. 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. There is a precision 0.8V reference and a power good output indicator. A wide 4V to 30V (36V maximum) input supply range encompasses all battery chemistries.A RUN/SS pin for each controller provides soft-start, and on the LTC3727GN, optional timed, short-circuit shutdown. Current foldback limits MOSFET heat dissipation during short-circuit conditions when overcurrent latchoff is disabled. Output overvoltage protection circuitry latches on the bottom MOSFET until VOUT returns to normal. The FCB mode pin can select among Burst Mode, constant frequency mode and continuous inductor current mode or regulate a secondary winding. Vin Range Vref Accuracy Over Temp Latch-Off  Min On-Time  LTC3727 4V - 36V ±1%   No   180ns  LTC3727-1 4V - 36V ±1%  Yes 180ns  LTC3727A-1 4V - 36V ±1%  No 120ns  LTC3727LX-1 4V - 32V ±1.5%  No 120ns Applications Telecom Systems Automotive Systems Battery-Operated Digital Devices

The LTC3727/LTC3727-1 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 phase-lockable frequency of up to 550kHz. 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. There is a precision 0.8V reference and a power good output indicator. A wide 4V to 30V (36V maximum) input supply range encompasses all battery chemistries.A RUN/SS pin for each controller provides soft-start, and on the LTC3727GN, optional timed, short-circuit shutdown. Current foldback limits MOSFET heat dissipation during short-circuit conditions when overcurrent latchoff is disabled. Output overvoltage protection circuitry latches on the bottom MOSFET until VOUT returns to normal. The FCB mode pin can select among Burst Mode, constant frequency mode and continuous inductor current mode or regulate a secondary winding. Vin Range Vref Accuracy Over Temp Latch-Off  Min On-Time  LTC3727 4V - 36V ±1%   No   180ns  LTC3727-1 4V - 36V ±1%  Yes 180ns  LTC3727A-1 4V - 36V ±1%  No 120ns  LTC3727LX-1 4V - 32V ±1.5%  No 120ns Applications Telecom Systems Automotive Systems Battery-Operated Digital Devices

The LTC3727LX-1 is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant-frequency current mode architecture allows phase-lockable frequency of up to 550kHz. 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. There is a precision 0.8V reference and a power good output indicator. A wide 4V to 28V (32V maximum) input supply range encompasses all battery chemistries. VIN Range VREF Accuracy Over Temp Latch-Off Min On-Time LTC3727 4V - 36V ±1% No 180ns LTC3727-1 4V - 36V ±1% Yes 180ns LTC3727A-1 4V - 36V ±1% No 120ns LTC3727LX-1 4V - 32V ±1.5% No 120ns Applications Telecom Systems Automotive Systems Distributed DC Power Systems

The LTC3729 is a multiple phase, synchronous step-down current mode switching regulator controller that drives 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 550kHz 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 latchoff is disabled. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3729 includes a power good output pin that indicates when the output is within ±7.5% of the designed set point. Vin Max Vref LTC3729 36V 0.8 LTC3729L-6 30V 0.6 Applications Desktop Computers Large Memory Arrays DC Power Distribution Systems