Description

The LTC3890 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 noise due to the ESR of the input capacitor are minimized by operating the two controller output stages out-of-phase. The 50?A no-load quiescent current extends operating run time 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 LTC3890 features a precision 0.8V reference and power good output indicators. 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 leaded package version (28-lead Narrow SSOP), see the LTC3890-1 data sheet. LTC3890 LTC3890-1 LTC3890-2 LTC3890-3 Adjustable Current Limit Limit Yes No Yes No CLKOUT/PHASMD for Multiphase Operation Yes No Yes No Number of PGood Outputs 2 1 2 1 OVP ? Bottom Gate Crowbar Yes Yes No No Current Limit Foldback Yes Yes No No Light Load Operation when Synced to External Clock Forced Continuous Forced Continuous Pulse Skipping Pulse Skipping SENSE Pins Common Mode Range Common Mode < 0.5V Requires VFB < 0.65V Common Mode < 0.5V Requires VFB < 0.65V Not Dependant on VFB. Easy to make a non-synchronous Boost or SEPIC Not Dependant on VFB. Easy to make a non-synchronous Boost or SEPIC Package 5 ? 5 QFN-32 SSOP-28 5 ? 5 QFN-32 SSOP-28 Applications Automotive Always-On Systems Battery Operated Digital Devices Distributed DC Power Systems

Type:

Part number: DC2236A-B

More details from Analog Devices Inc.