Analog Devices Inc./Maxim Integrated

The LTC3857-1 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 a phase-lockable frequency of up to 850kHz. Power loss and noise due to the ESR of the input capacitor ESR are minimized by operating the two controller output stages out of phase.The 50μA no-load quiescent current extends operating life in battery-powered systems. The LTC3857-1 features a precision 0.8V reference and a power good output indicator. wide 4V to 38V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.Independent TRACK/SS pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light loads.For a leadless 32-pin QFN package with the additional features of adjustable current limit, clock out, phase modulation and two PGOOD outputs, see the LTC3857 data sheet.LTC3857LTC3857-1FeaturesAdjustable Current Limit, Clock Output, Phase Modulation, 2 PGOOD OutputsFixed Current Limit, One PGOOD OutputPackageQFN-32SSOP-28ApplicationsAutomotive Always-On SystemsBattery Operated Digital DevicesDistributed DC Power Systems

The LTC3858-2 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 a phase-lockable frequency of up to 850kHz. Power loss and noise due to the input capacitor ESR are minimized by operating the two controller outputs out of phase.The 170μA no-load quiescent current extends operating life in battery-powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3858-2 differs from the LTC3858 by having the overvoltage protection crowbar and short-circuit latchoff disabled. A wide 4V to 38V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.Independent soft-start pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions.LTC3858LTC3858-1LTC3858-2FeaturesAdjustable Current Limit, Clock Output, Phase Modulation, 2 PGOOD OutputsFixed Current Limit, One PGOOD OutputOvervoltage protection crowbar and short-circuit latchoff disabledPackageQFN-32SSOP-28QFN-32ApplicationsAutomotive SystemsBattery Operated Digital DevicesDistributed DC Power Systems

The LTC3858-1 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 a phase-lockable frequency of up to 850kHz. Power loss and noise due to the input capacitor ESR are minimized by operating the two controller outputs out of phase.The 170μA no-load quiescent current extends operating life in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3858-1 features a precision 0.8V reference and a power good output indicator. A wide 4V to 38V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.Independent soft-start pins for each controller ramp the output voltages during start-up. The output latch-off feature protects the circuit in short-circuit conditions.For a leadless 32-pin QFN package with the additional features of adjustable current limit, clock out, phase modulation and two PGOOD outputs, see the LTC3858 data sheet.LTC3858LTC3858-1LTC3858-2FeaturesAdjustable Current Limit, Clock Output, Phase Modulation, 2 PGOOD OutputsFixed Current Limit, One PGOOD OutputOvervoltage protection crowbar and short-circuit latchoff disabledPackageQFN-32SSOP-28QFN-32ApplicationsAutomotive SystemsBattery Operated Digital DevicesDistributed DC Power Systems

The LTC3858-2 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 a phase-lockable frequency of up to 850kHz. Power loss and noise due to the input capacitor ESR are minimized by operating the two controller outputs out of phase.The 170μA no-load quiescent current extends operating life in battery-powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3858-2 differs from the LTC3858 by having the overvoltage protection crowbar and short-circuit latchoff disabled. A wide 4V to 38V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.Independent soft-start pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions.LTC3858LTC3858-1LTC3858-2FeaturesAdjustable Current Limit, Clock Output, Phase Modulation, 2 PGOOD OutputsFixed Current Limit, One PGOOD OutputOvervoltage protection crowbar and short-circuit latchoff disabledPackageQFN-32SSOP-28QFN-32ApplicationsAutomotive SystemsBattery Operated Digital DevicesDistributed DC Power Systems

The LTC3859AL is a high performance triple output (buck/buck/boost) synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Constant frequency current mode architecture allows a phase-lockable switching frequency of up to 850kHz. The LTC3859AL operates from a wide 4.5V to 38V input supply range. When biased from the output of the boost converter or another auxiliary supply, the LTC3859AL can operate from an input supply as low as 2.5V after start-up.The 28μA no-load quiescent current extends operating runtime in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3859AL features a precision 0.8V reference for the bucks, 1.2V reference for the boost and a power good output indicator. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light loads.Compared to the LTC3859 and the LTC3859A, the LTC3859AL is fully pin-compatible, but with lower Burst Mode operation IQ(28µA with one channel on).Quiescent Current (Burst Mode)NotesLTC3859AL28μA-One channel on, Buck38μA-All three channels onInternal clamp on the INTVCC pinLTC3859A55μA-One channel on, Buck80μA-All three channels onInternal clamp on the INTVCC pin. For new designs, we recommend LTC3859ALLTC385955μA-One channel on, Buck80μA-All three channels onFor new designs, we recommend LTC3859ALAPPLICATIONSAutomotive Always-On and Start-Stop SystemsBattery Operated Digital DevicesDistributed DC Power SystemsMultioutput Buck-Boost Applications

The LTC3859A is a high performance triple output (buck/buck/boost) synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Constant frequency current mode architecture allows a phase-lockable switching frequency of up to 850kHz. The LTC3859A operates from a wide 4.5V to 38V input supply range. When biased from the output of the boost converter or another auxiliary supply, the LTC3859A can operate from an input supply as low as 2.5V after start-up.The 55μA no-load quiescent current extends operating runtime in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3859A features a precision 0.8V reference for the bucks, 1.2V reference for the boost and a power good output indicator. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light loads.Compared to the LTC3859, the LTC3859A's boost controller has improved performance in Burst Mode operation when the input voltage is higher than the regulated output voltage.Quiescent Current (Burst Mode)NotesLTC3859AL28μA-One channel on, Buck38μA-All three channels onInternal clamp on the INTVCC pinLTC3859A55μA-One channel on, Buck80μA-All three channels onInternal clamp on the INTVCC pin. For new designs, we recommend LTC3859ALLTC385955μA-One channel on, Buck80μA-All three channels onFor new designs, we recommend LTC3859ALApplicationsAutomotive Always-On and Start-Stop SystemsBattery Operated Digital DevicesDistributed DC Power SystemsMultioutput Buck-Boost Applications

The LTC3859AL is a high performance triple output (buck/buck/boost) synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Constant frequency current mode architecture allows a phase-lockable switching frequency of up to 850kHz. The LTC3859AL operates from a wide 4.5V to 38V input supply range. When biased from the output of the boost converter or another auxiliary supply, the LTC3859AL can operate from an input supply as low as 2.5V after start-up.The 28μA no-load quiescent current extends operating runtime in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3859AL features a precision 0.8V reference for the bucks, 1.2V reference for the boost and a power good output indicator. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light loads.Compared to the LTC3859 and the LTC3859A, the LTC3859AL is fully pin-compatible, but with lower Burst Mode operation IQ(28µA with one channel on).Quiescent Current (Burst Mode)NotesLTC3859AL28μA-One channel on, Buck38μA-All three channels onInternal clamp on the INTVCC pinLTC3859A55μA-One channel on, Buck80μA-All three channels onInternal clamp on the INTVCC pin. For new designs, we recommend LTC3859ALLTC385955μA-One channel on, Buck80μA-All three channels onFor new designs, we recommend LTC3859ALAPPLICATIONSAutomotive Always-On and Start-Stop SystemsBattery Operated Digital DevicesDistributed DC Power SystemsMultioutput Buck-Boost Applications

The LTC3860 is a dual, PolyPhase®synchronous stepdown switching regulator controller for high current distributed power systems, digital signal processors, and other telecom and industrial DC/DC power supplies. It uses a constant frequency voltage mode architecture combined with very low offset, high bandwidth error amplifiers and a remote output sense differential amplifier for excellent transient response and output regulation.The controller incorporates lossless inductor DCR current sensing to maintain current balance between phases and to provide overcurrent protection. The chip operates from a VCCsupply between 3V and 5.5V and is designed for stepdown conversion from VINbetween 3V and 24V to output voltages between 0.6V and VCC– 0.5V.The TRACK/SS pins provide programmable soft-start or tracking functions. Inductor current reversal is disabled during soft-start to safely power prebiased loads. The constant operating frequency can be synchronized to an external clock or linearly programmed from 250kHz to 1.25MHz. Up to six LTC3860 controllers can operate in parallel for 1-, 2-, 3-, 4-, 6- or 12-phase operation.The LTC3860 is available in a 32-pin 5mm × 5mm QFN package.ApplicationsHigh Current Distributed Power SystemsDigital Signal Processor and ASIC SuppliesTelecom SystemsIndustrial Power Supplies

The LTC3861 is a dual PolyPhase®synchronous stepdown switching regulator controller for high current distributed power systems, digital signal processors, and other telecom and industrial DC/DC power supplies. It uses a constant-frequency voltage mode architecture combined with very low offset, high bandwidth error amplifiers and a remote output sense differential amplifier per channel for excellent transient response and output regulation.The controller incorporates lossless inductor DCR current sensing to maintain current balance between phases and to provide overcurrent protection. The chip operates from a VCCsupply between 3V and 5.5V and is designed for stepdown conversion from VINbetween 3V and 24V to output voltages between 0.6V and VCC– 0.5V.The TRACK/SS pins provide programmable soft-start or tracking functions. Inductor current reversal is disabled during soft-start to safely power prebiased loads. The constant operating frequency can be synchronized to an external clock or linearly programmed from 250kHz to 2.25MHz. Up to six LTC3861 controllers can operate in parallel for 1-, 2-, 3-, 4-, 6- or 12-phase operation.The LTC3861 is available in a 36-pin 5mm × 6mm QFN package. LTC3861-1 is a 32-pin QFN version of the LTC3861, which has a single differential remote output voltage sense amplifier.# Diff AmpsConfig PinPackageLTC38612Yes5 x 6 QFN-36LTC3861-11No5 x 5 QFN-32ApplicationsHigh Current Distributed Power SystemsDSP, FPGA and ASIC SuppliesDatacom and Telecom SystemsIndustrial Power Supplies