LTC3401 1A, 3MHz Micropower Synchronous Boost Converter FEATURES DESCRIPTIO Synchronous Rectification: Up to 97% Efficiency The LTC 3401 is a high efficiency, fixed frequency, step- 1A Switch Current Rating up DC/DC converter that operates from an input voltage Fixed Frequency Operation Up to 3MHz below 1V. The device includes a 0.16 N-channel MOSFET Wide Input Range: 0.5V to 5.5V (Operating) switch and a 0.18 P-channel synchronous rectifier. Very Low Quiescent Current: 38A (Burst Mode Switching frequencies up to 3MHz are programmed with Operation) an external timing resistor and the oscillator can be 2.6V to 5.5V Adjustable Output Voltage synchronized to an external clock. An external Schottky 0.85V (Typ) Start-Up Voltage diode is optional but will slightly improve efficiency. No External Schottky Diode Required (V < 4.3V) OUT Quiescent current is only 38A in Burst Mode operation, Synchronizable Switching Frequency maximizing battery life in portable applications. Burst Burst Mode Enable Control Mode operation is user controlled and can be enabled by Antiringing Control Reduces Switching Noise driving the MODE/SYNC pin high. If the MODE/SYNC pin PGOOD Output has either a clock or is driven low, then fixed frequency OPTI-LOOP Compensation switching is enabled. Very Low Shutdown Current: <1A Other features include 1A shutdown, antiringing control, Small 10-Pin MSOP Package U open-drain power good output, thermal shutdown and APPLICATIO S current limit. The LTC3401 is available in the 10-lead thermally enhanced MSOP package. Higher current appli- Pagers cations should use the 2A rated LTC3402 synchronous Handheld Instruments boost converter. Applications that require V < 2.6V OUT Cordless Phones should use the LTC3423. Wireless Handsets , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. GPS Receivers Burst Mode and OPTI-LOOP are registered trademarks of Linear Technology Corporation. Battery Backup CCFL Backlights TYPICAL APPLICATION All-Ceramic-Capacitor 2-Cell to 3.3V at 500mA Step-Up Converter L1 4.7H V = 1.8V to 3V V Efficiency OUT IN 3.3V 100 500mA Burst Mode LTC3401 90 OPERATION 3 4 R2 V SW IN 909k 80 1MHz 10 7 SHDN V FIXED OUT 70 + FREQUENCY 2 2 8 60 C2 CELLS MODE/SYNC FB 22F 50 6 9 PGOOD V C 40 C3 C1 1 470pF 5 R1 4.7F C4 30 R GND t 549k 4.7pF 20 R R5 t 30.1k 82k 10 V = 2.4V WITH SCHOTTKY IN 0 0.1 100 1000 110 3404 TA01 0 = FIXED FREQUENCY C1: TAIYO YUDEN JMK212BJ475MG I (mA) OUT 1 = Burst Mode OPERATION C2: TAIYO YUDEN JMK325BJ226MM 3401 TA02 L1: SUMIDA CD43-4R7M 3401fb 1 EFFICIENCY (%) U ULTC3401 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) V , V Voltages ...................................... 0.5V to 6V ORDER PART IN OUT TOP VIEW SW Voltage ................................................. 0.5V to 6V NUMBER R 1 10 SHDN t V , R Voltages ......................... 0.5V to (V + 0.3V) C t OUT MODE 2 9 V C LTC3401EMS V 3 8 FB PGOOD, SHDN, FB, MODE Voltages ........... 0.5V to 6V IN SW 4 7 V OUT Operating Temperature Range (Note 2) .. 40C to 85C GND 5 6 PGOOD Storage Temperature Range ................. 65C to 125C MS PACKAGE MS PART MARKING 10-LEAD PLASTIC MSOP Lead Temperature (Soldering, 10 sec).................. 300C T = 125C JMAX LTPG = 130C/ W 1 LAYER BOARD JA = 100C/ W 4 LAYER BOARD JA Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: