Datasheet LTC3409 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 600mA Low VIN Buck Regulator in 3mm × 3mm DFN |
| Pages / Page | 16 / 1 — FEATURES. DESCRIPTION. 1.6V to 5.5V Input Voltage Range. Internal … |
| File Format / Size | PDF / 295 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. 1.6V to 5.5V Input Voltage Range. Internal Soft-Start. Selectable 1.7MHz or 2.6MHz Constant Frequency
Model Line for this Datasheet
Text Version of Document
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
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
