Datasheet LTC3409 (Analog Devices)

FabricanteAnalog Devices
Descripción600mA Low VIN Buck Regulator in 3mm × 3mm DFN
Páginas / Página16 / 1 — FEATURES. DESCRIPTION. 1.6V to 5.5V Input Voltage Range. Internal …
Formato / tamaño de archivoPDF / 295 Kb
Idioma del documentoInglés

FEATURES. DESCRIPTION. 1.6V to 5.5V Input Voltage Range. Internal Soft-Start. Selectable 1.7MHz or 2.6MHz Constant Frequency

Datasheet LTC3409 Analog Devices

Línea de modelo para esta hoja de datos

Versión de texto del documento

LTC3409 600mA Low VIN Buck Regulator in 3mm × 3mm DFN
FEATURES DESCRIPTION

1.6V to 5.5V Input Voltage Range
The LTC®3409 is a high effi ciency, monolithic synchronous ■
Internal Soft-Start
buck regulator using a constant frequency, current mode ■
Selectable 1.7MHz or 2.6MHz Constant Frequency
architecture. The output voltage is adjusted via an external
Operation
resistor divider. ■
Internal Oscillator can be Synchronizable to an
Fixed switching frequencies of 1.7MHz and 2.6MHz are
External Clock, 1MHz to 3MHz Range
supported. Alternatively, an internal PLL will synchronize ■ High Effi ciency: Up to 95% to an external clock in the frequency range of 1MHz to ■ Very Low Quiescent Current: Only 65μA During 3MHz. This range of switching frequencies allows the Burst Mode® Operation use of small surface mount inductors and capacitors, ■ 600mA Output Current (VIN = 1.8V, VOUT = 1.2V) including ceramics. ■ 750mA Peak Inductor Current ■ No Schottky Diode Required Supply current during Burst Mode operation is only ■ Low Dropout Operation: 100% Duty Cycle 65μA dropping to <1μA in shutdown. The 1.6V to 5.5V ■ 0.613V Reference Voltage input voltage range makes the LTC3409 ideally suited ■ Stable with Ceramic Capacitors for single cell Li-Ion, Li-Metal and 2-cell alkaline, NiCd ■ Shutdown Mode Draws <1μA Supply Current or NiMH battery-powered applications. 100% duty cycle ■ Current Mode Operation for Excellent Line and Load capability provides low dropout operation, extending bat- Transient Response tery life in portable systems. Burst Mode operation can be ■ Overtemperature Protection user-enabled, increasing effi ciency at light loads, further ■ Available in a Low Profi le (0.75mm) 8-Lead extending battery life. (3mm × 3mm) DFN Package The internal synchronous switch increases effi ciency and eliminates the need for an external Schottky diode. Internal
APPLICATIONS
soft-start offers controlled output voltage rise time at start- up without the need for external components. ■ Cellular Phones ■ Digital Cameras , LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. ■ MP3 Players Protected by U.S. Patents, including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131.
TYPICAL APPLICATION Burst Mode Effi ciency, 1.8VOUT
100 1.0 90 2.5VIN, BURST
High Effi ciency Step-Down Converter
80 0.1 4.2V 70 IN, BURST POWER LOSS (W) 3.6V LTC3409 2.2μH* IN, BURST 60 V V IN V OUT IN SW 1.8V TO 5.5V 1.8V 4.7μF 10pF 50 0.01 RUN 10μF CER CER 40 MODE VFB EFFICIENCY (%) POWER LOST 255k 30 SYNC GND 133k 3.6VIN, BURST 0.001 20 10 *SUMIDA CDRH2D18/LD 3409 TA01 0 0.0001 0.1 1 10 100 1000 LOAD CURRENT (mA) 3409 TA01b 3409fc 1