LTC1911-1_8| Datasheet

Datasheet preview, take a look at Datasheets before downloading (Data Sheet is available on manufacturer site)

LTC1911-1.5/LTC1911-1.8 Low Noise, High Efficiency, Inductorless Step-Down DC/DC Converter

FEATURES
s s s s s s s s s s s s s

DESCRIPTIO

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 = 180uA Typ Low Shutdown Current: IIN = 10uA 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

The LTC 1911 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. A unique constant frequency architecture provides a low noise regulated output as well as lower input noise than conventional charge pump regulators. High frequency operation (fOSC = 1.5MHz) simplifies output filtering to further reduce conducted noise. To optimize efficiency, the part enters Burst Mode operation under light load conditions. Low operating current (180uA with no load, 10uA in shutdown) and low external parts count (two 1uF flying capacitors and two 10uF bypass capacitors) make the LTC1911 ideally suited for space constrained
batterypowered applications. The part is short-circuit and overtemperature protected, and is available in an 8-pin MSOP package.

APPLICATIO S
s s s s s s

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

, LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. *U.S. Patent #6,438,005

TYPICAL APPLICATIO

90

Single Cell Li-Ion to 1.8V DC/DC Converter
80 100mA LTC1911-1.8 2.7V TO 5.5V INPUT 1-CELL Li-Ion OR 3-CELL NiMH 10uF* 1uF* 1 2 3 4 *CERAMIC CAPACITOR 30 2 3 4 5 INPUT VOLTAGE (V) 6
1911 G05

VIN C2+ C2 GND

SS/SHDN VOUT C1+ C1

8 6 7 5 1uF*
1911 TA01

EFFICIENCY (%)

70 60 50 IDEAL LDO 40 VOUT = 1.8V

VOUT = 1.8V IOUT = 250mA 10uF*

U
Efficiency
250mA
1911f

U

U

1

LTC1911-1_8 Datasheet linear Download PDF

Add this permalink to your bookmarks for future download of LTC1911-1_8 datasheet

Permalink: http://datasheet.emcelettronica.com/linear/LTC1911-1_8

LTC1911-1_8 DATASHEET