LTC3525D-3.3 400mA Micropower Synchronous Step-Up DC/DC Converter with Pass Through Mode FeaTuresDescripTion n VOUT Connected to VIN in Shutdown The LTC®3525D-3.3 is a high efficiency synchronous step- n Up to 95% Efficiency up DC/DC converter that can start up with an input as low n 0.85V Minimum Input Start-Up Voltage as 0.85V. It offers a compact, high efficiency alternative to n Fixed Output Voltage of 3.3V charge pumps in single cell or dual cell alkaline or Li-Ion n Delivers 60mA at 3.3V from a 1V Input, applications. Only three small external components are re- or 140mA at 3.3V from a 1.8V Input quired. The LTC3525D features a fixed output voltage of 3.3V. n Burst Mode ® Operation: IQ = 7µA In shutdown, VOUT is connected to VIN through the inductor. n VIN Range: 0.5V to 4.5V The device includes a 0.5Ω N-channel MOSFET switch and n Only Three External Components a 0.8Ω P-channel synchronous rectifier. Peak switch current n VIN > VOUT Operation ranges from 150mA to 400mA, depending on load, providing n Anti-Ringing Control enhanced efficiency. Quiescent current is an ultralow 7µA, n Short-Circuit and Overtemperature Protection maximizing battery life in portable applications. n Very Low Profile of 1mm n Tiny 6-Lead SC70 Package Other features include anti-ringing control and thermal shutdown. The LTC3525D is available in a tiny 6-Lead applicaTions SC70 package. n MP3 Players List of LTC3525 Options n Portable Instruments PART NAMEINPUT START-UP OUTPUT VOUT STATUS IN n VOLTAGEVOLTAGESHUTDOWN MODE Glucose Meters n Digital Cameras LTC3525-3 0.85V 3V Output Disconnect L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks LTC3525-3.3 0.85V 3.3V Output Disconnect and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the LTC3525-5 0.85V 5V Output Disconnect property of their respective owners. Patents pending. LTC3525D-3.3 0.85V 3.3V Pass Through Mode LTC3525L-3 0.7V 3V Output Disconnect LTC3525D-3.3 Efficiency andTypical applicaTionPower Loss vs Load Current L1* 100 100 10µH 90 LTC3525D-3.3 80 10 POWER LOSS (mW) VIN EFFICIENCY VIN SW 1.8V TO 3.2V 70 VOUT PASS THROUGH ON SHDN V 3.3V OUT 60 1 140mA POWER LOSS GND GND EFFICIENCY (%) 50 1µF 10µF 40 0.1 VIN = 3V 3525 TA01 30 *MURATA LQH32CN100K53 VIN = 2.4V VIN = 1.2V 20 0.01 0.01 0.1 1 10 100 1000 LOAD (mA) LT3525 • TA02 3525d33fb For more information www.linear.com/LTC3525D3.3 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Typical Applications Package Description Revision History Related Parts