LTC3561A - 1A, 4MHz, Synchronous Step-Down DC/DC Converter

The LTC®3561A is a constant frequency, synchronous step-down DC/DC converter. Intended for medium power applications, it operates from a 2.5V to 5.5V input voltage range and has a user configurable operating frequency up to 4MHz, allowing the use of tiny, low cost capacitors and inductors 1mm or less in height. The output voltage is adjustable from 0.8V to 5.5V. Internal synchronous power switches provide high efficiency. The LTC3561A’s current mode architecture and external compensation allow the transient response to be optimized over a wide range of loads and output capacitors.

To further maximize battery life, the P-channel MOSFET is turned on continuously in dropout (100% duty cycle). In shutdown, the device draws <1μA.

Features

Uses Tiny Capacitors and Inductor
High Frequency Operation: Up to 4MHz
Low RDS(ON) Internal Switches: 0.15Ω
High Efficiency: Up to 96%
Stable with Ceramic Capacitors
Current Mode Operation for Excellent Line and Load Transient Response
Short-Circuit Protected
Low Dropout Operation: 100% Duty Cycle
Low Shutdown Current: IQ ≤ 1μA
Low Quiescent Current: 330μA
Output Voltages from 0.8V to 5V
VIN: 2.5V to 5.5V
Small 8-Lead 3mm × 3mm DFN Package

Typical Application

Applications

Notebook Computers
Digital Cameras
Cellular Phones
Handheld Instruments
Board Mounted Power Supplies

Packaging

Order Information

Part Number	Package	Temp	Price(1-99)	Price (1k)*
LTC3561AEDD#PBF	3x3 DFN-8	E	$2.50	$1.75
LTC3561AEDD#TRPBF	3x3 DFN-8	E		$1.81
LTC3561AIDD#PBF	3x3 DFN-8	I	$2.87	$2.01
LTC3561AIDD#TRPBF	3x3 DFN-8	I		$2.06

Demo Boards

Part Number	Description	Price
DC1072B	LTC3561AEDD Demo Board \| 2.5V ≤ VIN ≤ 5.5V, Vout = 1.2V/1.5V/1.8V/Adj @ 1A	$100.00