Analog Devices Inc./Maxim Integrated

The LTC3723-1/LTC3723-2 synchronous push-pull PWM controllers provide all of the control and protection functions necessary for compact and highly efficient, isolated power converters. High integration minimizes external component count, while preserving design flexibility.The robust push-pull output stages switch at half the oscillator frequency. Dead-time is independently programmed with an external resistor. Synchronous rectifier timing is adjustable to optimize efficiency. A UVLO program input provides precise system turn-on and turn off voltages. The LTC3723-1 features peak current mode control with programmable slope compensation and leading edge blanking, while the LTC3723-2 employs voltage mode control with voltage feedforward capability.The LTC3723-1/LTC3723-2 feature extremely low operating and start-up currents. Both devices provide reliable short-circuit and over temperature protection. The LTC3723-1/LTC3723-2 are offered in a 16-pin SSOP package.ApplicationsTelecommunications, Infrastructure Power SystemsDistributed Power Architectures

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 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.Vin RangeVref Accuracy Over TempLatch-OffMin On-TimeLTC37274V - 36V±1%No180nsLTC3727-14V - 36V±1%Yes180nsLTC3727A-14V - 36V±1%No120nsLTC3727LX-14V - 32V±1.5%No120nsApplicationsTelecom SystemsAutomotive SystemsBattery-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 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.Vin RangeVref Accuracy Over TempLatch-OffMin On-TimeLTC37274V - 36V±1%No180nsLTC3727-14V - 36V±1%Yes180nsLTC3727A-14V - 36V±1%No120nsLTC3727LX-14V - 32V±1.5%No120nsApplicationsTelecom SystemsAutomotive SystemsBattery-Operated Digital Devices

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 VOUTreturns to normal.VINRangeVREFAccuracy Over TempLatch-OffMin On-TimeLTC37274V - 36V±1%No180nsLTC3727-14V - 36V±1%Yes180nsLTC3727A-14V - 36V±1%No120nsLTC3727LX-14V - 32V±1.5%No120nsApplicationsTelecom SystemsAutomotive SystemsBattery-Operated Digital Devices

The LTC3728 is a dual high performance 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. 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 softstart 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 LTC3728 includes a power good output pin that indicates when both outputs are within 7.5% of their designed set point.Vin RangeVref AccyCurrent Limit Latch Off3.3V LDO AvailableLTC37283.5V to 36V+/-1%YesLTC3728L4.5V to 28V+/-1%YesYesLTC3728LX4.5V to 28V+/- 1.5%YesYesLTC3728L-14.5V to 28V+/- 1.5%Foldback onlyYesApplicationsNotebook and Palmtop ComputersTelecom SystemsPortable InstrumentsBattery-Operated Digital DevicesDC Power Distribution Systems

The LTC3728L-1 is a dual high performance 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 LTC3728L-1 is identical to the LTC3728L except that the LTC3728L-1 lacks the over current latch-off feature.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/35V for LTC3728LI-1) input supply range encompasses all battery chemistries.A RUN/SS pin for each controller provides soft-start. Current foldback limits MOSFET dissipation during shortcircuit conditions. The FCB mode pin can select among Burst Mode operation, constant frequency mode and continuous inductor current mode or regulate a secondary winding. The LTC3728L-1 includes a power good output pin that indicates when both outputs are within 7.5% of their designed set point.VINRangeVREFAccyCurrent Limit Latch Off3.3V LDO AvailableLTC37283.5V to 36V±1%YesLTC3728L4.5V to 28V±1%YesYesLTC3728LX4.5V to 28V±1.5%YesYesLTC3728L-14.5V to 28V±1.5%Foldback onlyYesApplicationsNotebook and Palmtop ComputersTelecom SystemsPortable InstrumentsBattery-Operated Digital DevicesDC Power Distribution Systems

The LTC3728L/LTC3728LX are dual high performance 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. 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 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 LTC3728L/LTC3728LX include a power good output pin that indicates when both outputs are within 7.5% of their designed set point.VinRangeVrefAccyCurrent Limit Latch Off3.3V LDO AvailableLTC37283.5V to 36V+/-1%YesLTC3728L4.5V to 28V+/-1%YesYesLTC3728LX4.5V to 28V+/- 1.5%YesYesLTC3728L-14.5V to 28V+/- 1.5%Foldback onlyYesApplicationsNotebook and Palmtop ComputersTelecom SystemsPortable InstrumentsBattery-Operated Digital DevicesDC Power Distribution Systems