LTC3890-1 Series

The LTC3890-1 is a high performance dual step-down switching regulator DC/DC 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 supply noise 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. OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. A wide 4V to 60V 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 conduction mode at light loads.For a leadless 32-pin QFN package with additional features of adjustable current limit, clock out, phase modulation and two PGOOD outputs, see the LTC3890 data sheet.LTC3890LTC3890-1LTC3890-2LTC3890-3Adjustable Current LimitLimitYesNoYesNoCLKOUT/PHASMD forMultiphase OperationYesNoYesNoNumber of PGoodOutputs2121OVP – Bottom GateCrowbarYesYesNoNoCurrent Limit FoldbackYesYesNoNoLight Load Operationwhen Synced to ExternalClockForced ContinuousForced ContinuousPulse SkippingPulse SkippingSENSE Pins CommonMode RangeCommon Mode < 0.5VRequires VFB < 0.65VCommon Mode < 0.5VRequires VFB < 0.65VNot Dependant onVFB. Easy to make anon-synchronousBoost or SEPICNot Dependant onVFB. Easy to make anon-synchronousBoost or SEPICPackage5 × 5 QFN-32SSOP-285 × 5 QFN-32SSOP-28ApplicationsAutomotive Always-On SystemsBattery Operated Digital DevicesDistributed DC Power Systems