LTC1612 Datasheet | Linear Technology

LT1612 Synchronous, Step-Down 800k Hz PWM DC/DC Converter Features s s s s s s s s DESCRIPTIO Operates from Input Voltage As Low As 2V Internal 0.7A Synchronous Switches Uses Ceramic Input and Output Capacitors 620m V Reference Voltage 800k Hz Fixed Frequency Switching Programmable Burst Mode Operation Low Quiescent Current: 160µA 8-Lead MSOP or SO Package U APPLICATIO S s s s s The LT®1612 is an 800k Hz, synchronous step-down DC/ DC converter that operates from an input voltage as low as 2V. Internal 0.45Ω switches deliver output currents up to 500m A, and the 800k Hz switching frequency allows the use of small, low value ceramic input and output capacitors. Input voltage ranges from 5.5V down to 2V and output voltage can be set as low as the 620m V reference. The device Features Burst Mode TM operation, keeping efficiency high at light loads. Burst Mode operation can be defeated by pulling the MODE pin high, enabling constant switching throughout the load range for low noise. No-load quiescent current is 160µA and shutdown current is less than 1µA. The device is available in 8-lead SO and MSOP packages. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. Portable Devices Lithium-Ion Step-Down Converters 5V to 3.3V Conversion 2-Cell Alkaline Step-Down Converters TYPICAL APPLICATION 0.1µF VIN 2V VIN SHDN LT1612 C1 10µF MODE VC 33.2k FB GND BOOST SW 100p F L1 10µH VOUT 1.2V 500m A Efficiency for LT1612 vs Linear Regulator VOUT = 1.2V 90 80 VIN = 2V VIN = 3V VIN = 2V (LINEAR) 330p F w w w .d h s a t a C1: TAIYO-YUDEN JMK325BJ106MN C2: PANASONIC EEFCDOF680R L1: SUMIDA CD43-100 ee . u t4 R2 232k 1% m o c EFFICIENCY (%) 70 60 50 40 R1 215k 1% C2 68µF 3.15V VIN = 3V (LINEAR) 10 100 LOAD CURRENT (m A) 500 - F01b 1612 F01a Figure 1. 2V to 1.2V Converter .. LT1612...