LTC3858 Series

Low IQ, Dual 2-Phase Synchronous Step-Down Controller

Manufacturer: Analog Devices Inc./Maxim Integrated

Catalog

Low IQ, Dual 2-Phase Synchronous Step-Down Controller

Part	Frequency - Switching [Min]	Frequency - Switching [Max]	Output Configuration	Function	Output Phases	Control Features	Supplier Device Package	Mounting Type	Duty Cycle (Max) [Max]	Operating Temperature [Min]	Operating Temperature [Max]	Topology	Number of Outputs	Output Type	Voltage - Supply (Vcc/Vdd) [Min]	Voltage - Supply (Vcc/Vdd) [Max]
Analog Devices Inc./Maxim Integrated LTC3858EUH#TRPBF	105 kHz 350 kHz	535 kHz 835 kHz	Positive	Step-Down	2	Current Limit Enable Frequency Control Power Good Soft Start	32-QFN (5x5)	Surface Mount	99.4 %	-40 C	125 °C	Buck	2	Transistor Driver	4 V	38 V
Analog Devices Inc./Maxim Integrated LTC3858IUH#PBF	105 kHz 350 kHz	535 kHz 835 kHz	Positive	Step-Down	2	Current Limit Enable Frequency Control Power Good Soft Start	32-QFN (5x5)	Surface Mount	99.4 %	-40 C	125 °C	Buck	2	Transistor Driver	4 V	38 V
Analog Devices Inc./Maxim Integrated LTC3858IUH#TRPBF	105 kHz 350 kHz	535 kHz 835 kHz	Positive	Step-Down	2	Current Limit Enable Frequency Control Power Good Soft Start	32-QFN (5x5)	Surface Mount	99.4 %	-40 C	125 °C	Buck	2	Transistor Driver	4 V	38 V
Analog Devices Inc./Maxim Integrated LTC3858EUH#PBF	105 kHz 350 kHz	535 kHz 835 kHz	Positive	Step-Down	2	Current Limit Enable Frequency Control Power Good Soft Start	32-QFN (5x5)	Surface Mount	99.4 %	-40 C	125 °C	Buck	2	Transistor Driver	4 V	38 V
Analog Devices Inc./Maxim Integrated LTC3858IUH-2#TRPBF	105 kHz 350 kHz	535 kHz 835 kHz	Positive	Step-Down	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start	32-QFN (5x5)	Surface Mount	99 %	-40 C	125 °C	Buck	2	Transistor Driver	4 V	38 V

Catalog

Low IQ, Dual 2-Phase Synchronous Step-Down Controller

Description

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