Specification	LTC3855IUJ#PBF

Clock Sync	False
Control Features	Power Good, Phase Control, Frequency Control, Tracking, Enable, Soft Start, Current Limit
Duty Cycle (Max) [Max]	95 %
Frequency - Switching [Max]	770 kHz
Frequency - Switching [Min]	250 kHz
Function	Step-Down
Mounting Type	Surface Mount
Number of Outputs	2
Operating Temperature [Max]	125 °C
Operating Temperature [Min]	-40 C
Output Configuration	Positive
Output Phases	2
Output Type	Transistor Driver
Package / Case	40-WFQFN Exposed Pad
Supplier Device Package	40-QFN (6x6)
Synchronous Rectifier	True
Topology	Buck
Voltage - Supply (Vcc/Vdd) [Max]	38 V
Voltage - Supply (Vcc/Vdd) [Min]	4.5 V

LTC3855 Series

Dual, Multiphase Synchronous DC/DC Controller with Differential Remote Sense

Part	Topology	Function	Output Configuration	Output Phases	Control Features	Mounting Type	Voltage - Supply (Vcc/Vdd) [Min]	Voltage - Supply (Vcc/Vdd) [Max]	Output Type	Operating Temperature [Min]	Operating Temperature [Max]	Package / Case	Package / Case	Duty Cycle (Max) [Max]	Number of Outputs	Supplier Device Package	Frequency - Switching [Max]	Frequency - Switching [Min]
Analog Devices Inc./Maxim Integrated LTC3855IFE#TRPBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 C	125 °C	38-TFSOP Exposed Pad	0.173 " 4.4 mm	95 %	2	38-TSSOP-EP	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855IUJ	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 C	125 °C	40-WFQFN Exposed Pad		95 %	2	40-QFN (6x6)	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855IUJ#TRPBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 C	125 °C	40-WFQFN Exposed Pad		95 %	2	40-QFN (6x6)	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855EFE#TRPBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 ¯C	85 C	38-TFSOP Exposed Pad	0.173 " 4.4 mm	95 %	2	38-TSSOP-EP	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855IUJ#PBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 C	125 °C	40-WFQFN Exposed Pad		95 %	2	40-QFN (6x6)	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855EFE	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 ¯C	85 C	38-TFSOP Exposed Pad	0.173 " 4.4 mm	95 %	2	38-TSSOP-EP	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855EFE#PBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 ¯C	85 C	38-TFSOP Exposed Pad	0.173 " 4.4 mm	95 %	2	38-TSSOP-EP	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855EUJ#TRPBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 ¯C	85 C	40-WFQFN Exposed Pad		95 %	2	40-QFN (6x6)	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855EUJ#PBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 ¯C	85 C	40-WFQFN Exposed Pad		95 %	2	40-QFN (6x6)	770 kHz	250 kHz
Analog Devices Inc./Maxim Integrated LTC3855IFE#PBF	Buck	Step-Down	Positive	2	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Surface Mount	4.5 V	38 V	Transistor Driver	-40 C	125 °C	38-TFSOP Exposed Pad	0.173 " 4.4 mm	95 %	2	38-TSSOP-EP	770 kHz	250 kHz

Pricing

Prices provided here are for design reference only. For realtime values and availability, please visit the distributors directly

Distributor	Package	Quantity	$	Updated

Digikey	N/A	4537	$ 9.58	1m+
Newark	Each	1	$ 8.82	1m+
		10	$ 6.40
		25	$ 6.06
		50	$ 5.79
		122	$ 5.55

Description

General part information

LTC3855 Series

The LTC3855 is a dual PolyPhase®current mode synchronous step-down switching regulator controller that drives all N-channel power MOSFET stages. It includes a high speed differential remote sense amplifier. The maximum current sense voltage is programmable for either 30mV, 50mV or 75mV, allowing the use of either the inductor DCR or a discrete sense resistor as the sensing element.The LTC3855 features a precision 0.6V reference and can produce output voltages up to 12.5V. A wide 4.5V to 38V input supply range encompasses most intermediate bus voltages and battery chemistries. Power loss and supply noise are minimized by operating the two controller output stages out of phase. Burst Mode®operation, continuous or pulse-skipping modes are supported.The LTC3855 can be configured for up to 12-phase operation, has DCR temperature compensation, two power good signals and two current limit set pins. The LTC3855 is available in low profile 40-pin 6mm × 6mm QFN and 38-lead exposed pad FE packages.ApplicationsComputer SystemsTelecom SystemsIndustrial and Medical InstrumentsDC Power Distribution Systems

Documents

Technical documentation and resources

Technical Data Sheet EN

Datasheet

R526 Reliability Data

Reliability Data