SP6651A High Efficiency 800mA Synchronous Buck Regulator Ideal for portable designs powered with Li Ion battery FEATURES PV 1 10 LX IN DFN Package (3mm x 3mm) V 2 9 Ultra-low 20A Quiescent Current IN P SP6651A GND 98% Efficiency Possible BLON 3 8 GND 10 Pin DFN 800mA Output Current D1 4 7 V 2.7V to 5.5V Input Voltage Range OUT Output Adjustable Down to 1.0V 6 D0 5 FB No External FETs Required 1.25A Inductor Peak Current Limit Now Available in Lead Free Packaging 100% Duty Ratio Low Dropout Operation 80A Light Load Quiescent Current APPLICATIONS in Dropout PDA s Over Temperature Protection DSC s Logic Shutdown Control MP3 Players Programmable UVLO and Adaptive Battery Low Output USB Devices Point of Use Power DESCRIPTION The SP6651A is a 800mA synchronous buck regulator which is ideal for portable applications that use a Li-Ion or 3 cell alkaline/NiCD/NiMH input. The SP6651As proprietary control loop, 20A light load quiescent current, and 0.3 power switches provide excellent efficiency across a wide range of output currents. As the input battery supply decreases towards the output voltage the SP6651A seamlessly transitions into 100% duty ratio operation further extending useful battery life. The SP6651A is protected against overload and short circuit conditions with a precise inductor peak current limit. Other features include programmable under voltage lockout and low battery detection, externally programmed output voltage down to 1.0V, logic level shutdown control, and 140C over temperature shutdown. TYPICAL APPLICATION SCHEMATIC 2.7V to 5.5V Input L1 V OUT 10H 800mA VI 10 VO C IN R SP6651A VIN C OUT P LX VIN CV 22F IN 22F P V GND IN 1M 1F CF BLON GND 22pF R F BLON D1 D1 V OUT D0 D0 FB R I 200K Date: 5/25/04 SP6651A High Efficiency 800mA Synchronous Buck Regulator Copyright 2004 Sipex Corporation 1ABSOLUTE MAXIMUM RATINGS PV ,V .............................................................................................. 6V These are stress ratings only and functional operation of the device at IN IN All other pins .............................................................. -0.3V to V +0.3V these ratings or any other above those indicated in the operation IN PV , P , LX current ........................................................................ 2A sections of the specifications below is not implied. Exposure to IN GND Storage Temperature .................................................. -65 C to 150 C absolute maximum rating conditions for extended periods of time may Operating Temperature ................................................. -40C to +85C affect reliability. Lead Temperature (Soldering, 10 sec) ....................................... 300 C Thermal Resistance : JA 10-Pin MSOP....................................................................128C/W 10-Pin DFN ........................................................................68C/W ELECTRICAL CHARACTERISTICS V =UV =V =3.6V, V =V , I = 0mA, T = -40C to +85C, typical values at 27C unless otherwise noted. IN IN SDN OUT FB O AMB PARAMETER MIN TYP MAX UNITS CONDITIONS Input Voltage Operating UVLO 5.5 V Result of I measurement at V =PV =5.5V Q IN IN Range Minimum Output Voltage 1.0 V FB Set Voltage, Vr 0.784 0.800 0.816 V 25C, I =200mA Close Loop. L = 10H, O I C = 22F OUT Overall Accuracy Measured at V =5.5V, no load and IN (-40C to 85C) 5% V =3.6V, 200mA load, Close Loop IN (0C to 70C) 4 On-Time Constant - K 1.5 2.25 3.0 V*s Close Loop, L = 10H,C = 22F ON I OUT Min, T =K /(V -V ) ON ON IN OUT Off-Time Constant - K 1.6 2.4 3.2 V*s Inductor current limit tripped, VFB=0.5V OFF Min, T =K /V Measured at V = 2V OFF OFF OUT OUT Off-Time Blanking 100 ns PMOS Switch Resistance 0.3 0.6 I = 200mA PMOS NMOS Switch Resistance 0.3 0.6 I = 200mA NMOS Inductor Current Limit 1.0 1.25 1.50 A VFB=0.5V LX Leakage Current 0.01 3 A D0=D1=0 Power Efficiency 96 % V =2.5V, I =200mA OUT O 92 V =3.3V, I =800mA OUT O Minimum Guaranteed Load 800 900 mA Current V Quiescent Current 20 30 AV =3.3V, V =3.6V and V = 5.5V IN OUT IN IN V Shutdown Current 1 500 nA D1=D0=0V IN V Quiescent Current 2 5 AV = 3.3V OUT OUT V Shutdown Current 1 500 nA D1=D0=0V OUT UVLO 2.55 2.70 2.85 D1=0V, D0=V IN Undervoltage Lockout 2.70 2.85 3.00 V D1=V , D0=0V IN Threshold, V falling 2.85 3.00 3.15 D1=V , D0=V IN IN IN UVLO hysteresis 40 mV Battlo Trip Voltage, V falling 265 300 335 mV Measured as V -V IN IN OUT Battlo Trip Voltage Hysteresis 9 mV BLON Low Output Voltage 0.4 V V =3.3V, I =1mA IN SINK BLON Leakage Current 1 AV =3.6V BLON Over-Temperature 140 C Rising Trip Point Over-Temperature Hysteresis 14 C D1,D0 Leakage Current 1 500 nA D1,D0 Input Threshold Voltage 0.60 0.90 V High to Low Transition 1.25 1.8 V Low to High Transition FB Leakage Current 1 100 nA FB=1V Date: 5/25/04 SP6651A High Efficiency 800mA Synchronous Buck Regulator Copyright 2004 Sipex Corporation 2