LTC1911 - Low Noise, High Efficiency, Inductorless Step-Down DC/DC Converter

The LTC1911 is a switched capacitor step-down DC/DC converter that produces a 1.5V or 1.8V regulated output from a 2.7V to 5.5V input. The part uses switched capacitor fractional conversion to achieve high efficiency over the entire input range. No inductors are required. Internal circuitry controls the step-down conversion ratio to optimize efficiency as the input voltage and load conditions vary. Typical efficiency is over 25% higher than that of a linear regulator.

Low operating current (180µA with no load, 10µA in shutdown) and low external parts count (two 1µF flying capacitors and two 10µF bypass capacitors) make theLTC1911 ideally suited for space constrained battery powered applications. The part is short-circuit and over temperature protected, and is available in an 8-pin MSOP package.

Features

Low Noise Constant Frequency Operation
2.7V to 5.5V Input Voltage Range
No Inductors
Typical Efficiency 25% Higher Than LDOs
Shutdown Disconnects Load from VIN
Output Voltage: 1.8V ±4% or 1.5V ±4%
Output Current: 250mA
Low Operating Current: IIN = 180µA Typ
Low Shutdown Current: IIN = 10µA Typ
Oscillator Frequency: 1.5MHz
Soft-Start Limits Inrush Current at Turn On
Short-Circuit and Overtemperature Protected
Available in an 8-Pin MSOP Package

Typical Application

Applications

Handheld Computers
Cellular Phones
Smart Card Readers
Portable Electronic Equipment
Handheld Medical Instruments
Low Power DSP Supplies

Packaging

Order Information

Part Number	Package	Temp	Price(1-99)	Price (1k)*
LTC1911EMS8-1.5#PBF	MS-8	E	$2.77	$2.34
LTC1911EMS8-1.5#TRPBF	MS-8	E		$2.40
LTC1911EMS8-1.8#PBF	MS-8	E	$2.77	$2.34
LTC1911EMS8-1.8#TRPBF	MS-8	E		$2.40

Demo Boards

Part Number	Description	Price
DC342A-A	LTC1911EMS8-1.8 \| Low Noise, Constant Frequency Step-Down Charge Pump	Contact Factory
DC342A-B	LTC1911EMS8-1.5 \| Low Noise, Constant Frequency Step-Down Charge Pump	Contact Factory