LTC3864 - 60V Low IQ Step-Down DC/DC Controller with 100% Duty Cycle Capability

The LTC®3864 is a robust, high voltage step-down DC/DC controller optimized for automotive and industrial applications. It drives a P-channel power MOSFET switch allowing 100% duty cycle operation. The wide input and output voltage ranges cover a multitude of applications. This device has been verified with the failure mode and effects analysis (FMEA) procedure for operation during failure conditions.

The LTC3864 offers excellent light load efficiency, drawing only 40μA quiescent current in a user programmable Burst Mode operation. Its peak current mode, constant frequency PWM architecture provides for good control of switching frequency and output current limit. The switching frequency can be programmed from 50kHz to 850kHz with an external resistor and can be synchronized to an external clock from 75kHz to 750kHz.

The LTC3864 offers programmable soft-start or output tracking. Safety features include overvoltage protection, overcurrent and short-circuit protection including frequency foldback and a power good output signal.

The LTC3864 is available in thermally enhanced 12-Pin MSOP and 3mm × 4mm DFN packages.

Features

Wide Operating VIN Range: 3.5V to 60V
Wide VOUT Range: 0.8V to VIN
Low Operating IQ = 40μA
Very Low Dropout Operation: 100% Duty Cycle
Strong High Voltage MOSFET Gate Driver
Constant Frequency Current Mode Architecture
Verified FMEA for Adjacent Pin Open/Short
Selectable High Efficiency Burst Mode® Operation or Pulse-Skipping Mode at Light Loads
Programmable Fixed Frequency: 50kHz to 850kHz
Phase-Lockable Frequency: 75kHz to 750kHz
Accurate Current Limit
Programmable Soft-Start or Voltage Tracking
Internal Soft-Start Guarantees Smooth Start-Up
Power Good Output Voltage Monitor
Low Shutdown IQ = 7μA
Available in Small 12-Pin Thermally Enhanced MSOP and DFN Packages

Typical Application

Applications

Industrial and Automotive Power Supplies
Telecom Power Supplies
Distributed Power Systems

Packaging

**Order Information**
Part Number	Package	Temp	Price(1-99)	Price (1k)*
LTC3864EDE#PBF	4x3 DFN-12	E	$2.94	$2.06
LTC3864EDE#TRPBF	4x3 DFN-12	E		$2.12
LTC3864EMSE#PBF	MS-12E	E	$2.94	$2.06
LTC3864EMSE#TRPBF	MS-12E	E		$2.12
LTC3864HDE#PBF	4x3 DFN-12	H	$3.90	$2.73
LTC3864HDE#TRPBF	4x3 DFN-12	H		$2.79
LTC3864HMSE#PBF	MS-12E	H	$3.90	$2.73
LTC3864HMSE#TRPBF	MS-12E	H		$2.79
LTC3864IDE#PBF	4x3 DFN-12	I	$3.49	$2.44
LTC3864IDE#TRPBF	4x3 DFN-12	I		$2.50
LTC3864IMSE#PBF	MS-12E	I	$3.49	$2.44
LTC3864IMSE#TRPBF	MS-12E	I		$2.50
LTC3864MPDE#PBF	4x3 DFN-12	MP	$9.40	$6.58
LTC3864MPDE#TRPBF	4x3 DFN-12	MP		$6.64
LTC3864MPMSE#PBF	MS-12E	MP	$9.40	$6.58
LTC3864MPMSE#TRPBF	MS-12E	MP		$6.64

Demo Boards


Part Number	Description	Price
DC1722A	LTC3864EMSE Demo Board \| 5.5V ≤ VIN ≤ 55V; VOUT = 5V @ 2A	$100.00
DC2434A	LTC3864 Demo Board \| Buck Controller, 12V ≤ VIN ≤ 60V, Vout = 12V @ 5A	Contact Factory