POWER LOSS (W) LTC3544B Quad Synchronous Step-Down Regulator: 2.25MHz, 300mA, 200mA, 200mA, 100mA Fae Tseru Dpircse Tnoi High Efficiency: Up to 95% The LTC 3544B is a quad, high efficiency, monolithic Four Independent Regulators Provide Up to 300mA, synchronous buck regulator using a constant frequency, 200mA, 200mA and 100mA Output Current current mode architecture. The four regulators operate in- 2.25V to 5.5V Input Voltage Range dependently with separate run pins. The 2.25V to 5.5V input 2.25MHz Constant Frequency Operation voltage range makes the LTC3544B well suited for single No Schottky Diodes Required Li-Ion/polymer battery-powered applications. 100% duty Low Dropout Operation: 100% Duty Cycle cycle provides low dropout operation, extending battery Pulse Skipping at Low Load for Minimum Ripple runtime in portable systems. At moderate and low output 0.8V Reference Allows Low Output Voltages load levels PWM pulse skip mode operation provides very Shutdown Mode Draws <1A Supply Current low output ripple voltage for noise sensitive applications. Current Mode Operation for Excellent Line and Load Switching frequency is internally set to 2.25MHz, al- Transient Response lowing the use of small surface mount inductors and Overtemperature Protected capacitors. Low Profile (3mm 3mm) 16-Lead QFN Package The internal synchronous switches increase efficiency and eliminate the need for external Schottky diodes. Low a acilpp Tsnoi output voltages are easily supported with the 0.8V feedback Cellular Telephones reference voltage. Personal Information Appliances The LTC3544B is available in a low profile (0.75mm) Wireless and DSL Modems (3mm 3mm) QFN package. Digital Still Cameras L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Media Players Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 6580258, 6304066, 6127815, 6498466, Portable Instruments 6611131, 5994885. T lacipy a acilpp Tnoi High Efficiency Quad Step-Down Converter Efficiency vs Load Current, 300mA Channel, All Other Channels Off V IN 2.25V TO 5.5V 100 1 4.7F V = 1.5V OUT CER V PV 90 T = 25C A CC IN RUN200B RUN200A 4.7H 3.3H 80 V V OUT2 OUT3 SW200B SW200A 1.5V 0.8V 93.1k 70 0.1 EFFICIENCY V V FB200B FB200A 60 4.7F 4.7F 100k 107k CER CER 50 LTC3544B POWER LOSS 40 0.01 RUN300 RUN100 3.3H 10H 30 V V OUT4 OUT1 SW300 SW100 1.8V 1.2V 20 133k 59k V = 2.5V IN V V FB300 FB100 V = 3.6V 10 IN 4.7F 4.7F GNDA PGND V = 4.3V 107k 118k IN CER CER 0 0.001 0.0001 0.001 0.01 0.1 1 LOAD CURRENT (A) 3544B TA01a 3544B TA01b 3544bfb EFFICIENCY (%)LTC3544B a ulosb T e Mixa Mu M r a Tsgni p ni c no Farugi Tnoi (Note 1) Input Supply Voltage .....................................0.3V to 6V TOP VIEW RUNx ............................................. 0.3V to (V + 0.3V) IN V ............................................... 0.3V to (V + 0.3V) FBx IN SWx ............................................... 0.3V to (V + 0.3V) 16 15 14 13 IN V 1 12 RUN100 300mA P-Channel Source Current (DC) (Note 8) . 450mA FB200B V 2 11 V FB200A FB100 300mA N-Channel Sink Current (DC) (Note 8) ..... 450mA 17 GNDA RUN200A 3 10 V FB300 200mA P-Channel Source Current (DC) (Note 8) . 300mA SW200B 4 9 RUN300 200mA N-Channel Sink Current (DC) (Note 8) ..... 300mA 5 6 7 8 100mA P-Channel Source Current (DC) (Note 8) . 200mA 100mA N-Channel Sink Current (DC) (Note 8) ..... 200mA Peak 300mA SW Sink and Source Current UD PACKAGE (Note 8) ............................................................... 600mA 16-LEAD (3mm 3mm) PLASTIC QFNs T = 125C, = 68C/W JMAX JA Peak 200mA SW Sink and Source Current EXPOSED PAD (PIN 17) IS ANALOG GND, MUST BE SOLDERED TO PCB (Note 8) ............................................................... 400mA Peak 100mA SW Sink and Source Current (Note 8) ............................................................... 200mA Operating Temperature Range .................. 40C to 85C Junction Temperature (Notes 3, 4) ........................ 125C Storage Temperature Range ....................65C to 125C o r D re i n Fro Ma Tnoi LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3544BEUD PBF LTC3544BEUD TRPBF LCLN 40C to 85C 16-Lead (3mm 3mm) Plastic QFN LEAD BASED FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3544BEUD LTC3544BEUD TR LCLN 16-Lead (3mm 3mm) Plastic QFN 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. For more information on lead free part marking, go to: