Specification	LTC3850IUFD#PBF

Clock Sync	False
Control Features	Soft Start, Enable, Frequency Control, Power Good, Tracking, Current Limit
Duty Cycle (Max) [Max]	97.2 %
Frequency - Switching [Max]	780 kHz
Frequency - Switching [Min]	250 kHz
Function	Step-Down
Mounting Type	Surface Mount
Number of Outputs	2
Operating Temperature [Max]	85 C
Operating Temperature [Min]	-40 ¯C
Output Configuration	Positive
Output Phases	2
Output Type	Transistor Driver
Package / Case	28-WFQFN Exposed Pad
Supplier Device Package	28-QFN (4x5)
Synchronous Rectifier	True
Topology	Buck
Voltage - Supply (Vcc/Vdd) [Max]	30 V
Voltage - Supply (Vcc/Vdd) [Min]	4 V

LTC3850 Series

Dual, 2-Phase Synchronous Step-Down Switching Controller

Part	Voltage - Supply (Vcc/Vdd) [Max]	Voltage - Supply (Vcc/Vdd) [Min]	Function	Mounting Type	Output Type	Supplier Device Package	Number of Outputs	Duty Cycle (Max) [Max]	Topology	Operating Temperature [Max]	Operating Temperature [Min]	Package / Case [x]	Package / Case [y]	Package / Case	Frequency - Switching [Min]	Frequency - Switching [Max]	Control Features	Output Configuration	Output Phases
Analog Devices Inc./Maxim Integrated LTC3850EGN#PBF	24 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-SSOP	2	97.2 %	Buck	85 C	-40 ¯C	0.154 in	3.9 mm	28-SSOP	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850IUF#TRPBF	30 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-QFN (4x4)	2	97.2 %	Buck	85 C	-40 ¯C			28-WFQFN Exposed Pad	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850IGN-2#TRPBF	30 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-SSOP	2	97.2 %	Buck	85 C	-40 ¯C	0.154 in	3.9 mm	28-SSOP	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850EUFD#PBF	24 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-QFN (4x5)	2	97.2 %	Buck	85 C	-40 ¯C			28-WFQFN Exposed Pad	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850IUFD#PBF	30 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-QFN (4x5)	2	97.2 %	Buck	85 C	-40 ¯C			28-WFQFN Exposed Pad	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850IGN-2#PBF	30 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-SSOP	2	97.2 %	Buck	85 C	-40 ¯C	0.154 in	3.9 mm	28-SSOP	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850IGN#TRPBF	30 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-SSOP	2	97.2 %	Buck	85 C	-40 ¯C	0.154 in	3.9 mm	28-SSOP	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850IUF#PBF	30 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-QFN (4x4)	2	97.2 %	Buck	85 C	-40 ¯C			28-WFQFN Exposed Pad	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850EGN#TRPBF	24 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-SSOP	2	97.2 %	Buck	85 C	-40 ¯C	0.154 in	3.9 mm	28-SSOP	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2
Analog Devices Inc./Maxim Integrated LTC3850EUF#PBF	24 V	4 V	Step-Down	Surface Mount	Transistor Driver	28-QFN (4x4)	2	97.2 %	Buck	85 C	-40 ¯C			28-WFQFN Exposed Pad	250 kHz	780 kHz	Current Limit Enable Frequency Control Power Good Soft Start Tracking	Positive	2

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	0	$ 8.77	1m+
	Tube	146	$ 4.61	1m+

Description

General part information

LTC3850 Series

The LTC3850-2 is a high performance dual synchronous step-down switching regulator controller that drives all N-channel power MOSFET stages. A constant-frequency current mode architecture allows a phase-lockable frequency of up to 780kHz. Power loss and supply noise are minimized by operating the two controller output stages out of phase.OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3850-2 features a precision 0.8V reference and a power good output indicator. A wide 4V to 30V input supply range encompasses most battery chemistries and intermediate bus voltages.Independent TK/SS pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The MODE/PLLIN pin selects among Burst Mode®operation, pulse-skipping mode, or continuous inductor current mode and allows the IC to be synchronized to an external clock.The LTC3850-2 is identical to the LTC3850-1, except they have different pin assignments.FeaturesLTC3850SSOP-28 and QFN-28 PackagesLTC3850-1ILIM function replaced with an EXTVCC function, SSOP-28 package onlyLTC3850-2The LTC3850-2 is identical to the LTC3850-1 SSOP-28, except they have different pin-outsAPPLICATIONSNotebook and Palmtop ComputersPortable InstrumentsBattery-Operated Digital DevicesDC Power Distribution Systems

Documents

Technical documentation and resources

LTpowerPlanner III Quick Start Guide

Datasheet

R526 Reliability Data

Reliability Data