SP6649

SP6649 SIPEX | Alldatasheet

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Technical content

Rev:001 Date:11/20/03 SP6649 Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator © Copyright 2002 Sipex Corporation ADVANCED INFORMATION SP6649

FEATURES

■ Ultra-low 12µA Quiescent Current ■ 700mA Output Current at 2.6VIN, 3.3VOUT ■ 94% Efficiency Possible ■ Wide Input Voltage Range: 0.85V to 4.5V ■ 3.3V Fixed Output and adjustable 2.5V to 5.0V Output Range ■ Internal Synchronous Rectifier for High Efficiency ■ 0.3 Charging Switch, 0.3 Synchro- nous Rectifier ■ Anti-Ringing Inductor Switch ■ Programmable Inductor Peak Current ■ Logic Shutdown Control ■ Under Voltage Lock-Out, 0.62V ■ Programmable Low Battery Detect ■ Small 10 pin MSOP Package Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator

APPLICATIONS

■ Digital Still Cameras ■ MP3 Players ■ PDA's ■ Pagers ■ Handheld Portable Devices ■ Medical Monitors

DESCRIPTION

The SP6649 is an ultra-low quiescent current, high efficiency step-up DC-DC converter ideal for single and dual cell alkaline, or Li-Ion battery applications such as digital still cameras, PDA’s, MP3 players, and other portable devices. The SP6649 combines the high delivery associated with PWM control, and the low quiescent current and excellent light-load efficiency of PFM control. The SP6649 features 12µA quiescent current, synchronous rectification, a 0.3 charging switch, anti-ringing inductor switch, programmable low battery detect, under-voltage lockout and programmable inductor peak current. The device can be controlled by a 1nA active LOW shutdown pin. VBATT LBI LBON R LIM SHDN VOUT LX P GND GND FB Top View 10 pin MSOP Tja=113°C/W 47uF L1 10uHVBATT 47pF LBI SHDN 205K + C2 47uF RLIM 1.87K 3.3Vout 124K 1uF SP6649 5 6 10VBATT LBI RLIM SHDN FB GND PGNDLBON LX VOUT LBON C1 = C2 = Kemet T49C476K010AS, L1 = Sumida CDRH5D28-100 R1 = 374K for 5VOUT Figure 1. Typical Application Circuit Figure 2. Maximum Load Current in Operation

Rev:001 Date:11/20/03 SP6649 Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator © Copyright 2002 Sipex Corporation ADVANCED INFORMATION PARAMETER MIN TYP MAX UNITS CONDITIONS Input Voltage Operating Range, VBATT 0.7 4.5 V After Startup Under Voltage Lock-out/UVLO 0.62 V Start-up Input Voltage, VBATT 0.85 0.9 V R LOAD = 3k Output Voltage, VO 3.16 3.30 3.44 V 3.3V V O preset Quiescent Current into VO , IQO 12 22 µA V OUT = 3.3V, VFB = 1.5V, Toggle SHDN Quiescent Current into VBATT , IQB 20 500 nA V OUT = 3.3V, VFB = 1.5V Shutdown Current into VO, ISDO 1 500 nA V SHDN = 0V Shutdown Current into VBATT, ISDB 200 500 nA V SHDN = 0V, VBATT = 2.6V Efficiency, RLIM = 4.0K 85 % V BATT = 1.3V, IOUT = 50mA 91 % V BATT = 2.6V, IOUT = 100mA Efficiency, RLIM = 1.87K 85 % V BATT = 1.3V, IOUT = 100mA 92 % V BATT = 2.6V, IOUT = 200mA Inductor Current Limit, IPK 1.0 1.2 1.4 A R LIM = 1.17k , IPK = 1400/RLIM 250 mA V BATT = 1.3V, RLIM = 1.17k Output Current 700 mA V BATT = 2.6V, RLIM = 1.17k 150 mA V BATT = 1.3V, RLIM = 1.87k 400 mA V BATT = 2.6V, RLIM = 1.87k Minimum Off-Time Constant KOFF 1.1 V*µs t OFF KOFF / (VOUT - VBATT ) Maximum On-Time Constant KON 3.3 V*µs t ON KON / VBATT N MOS Switch Resistance 0.30 0.6 I NMOS = 100mA PMOS Switch Resistance 0.30 0.6 I PMOS = 100mA FB Set Voltage, VFB 1.20 1.25 1.30 V External feedback FB Input Current 1 100 nA V FB =1.3V LBI Falling Trip Voltage 0.594 0.625 0.656 V LBI Hysteresis 25 mV Low Output Voltage for LBON, VOL 0.4 V V BATT = 1.3V, Isink = 1mA Leakage current for LBON 500 nA V BATT = 1.3V, VLBON = 3.3V SHDN Input Voltage V IL 0.25 V BATT = 1.3V VIH 1.0 V V BATT = 1.3V VIL 0.5 V BATT = 2.6V VIH 2.0 V BATT = 2.6V SHDN Input Current 1 100 nA SPECIFICATIONS V BATT =V SHDN = 1.3V, VFB =0V, ILOAD = 0mA, TAMB = -40°C to +85°C, VOUT = +3.3V, typical values at 27°C unless otherwise noted. ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.

Rev:001 Date:11/20/03 SP6649 Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator © Copyright 2002 Sipex Corporation ADVANCED INFORMATION PIN DESCRIPTION PIN NUMBER PIN NAME DESCRIPTION 1V BATT Battery Voltage pin. The startup circuitry runs off of this pin. The operate circuit also uses this voltage to regulate the off-time OFF = KOFF / (VOUT - VBATT )]. When the battery voltage drops below 0.62V after a successful startup the SP6649 goes into an undervoltage lockout mode (UVLO). 2 LBI Low Battery Input pin. LBI below 0.61V causes the LBON pin to pull down to ground. Use a resistor divider to program the low voltage threshold for each battery configuration. 3 LBON Low Battery Output Not pin. Open drain N MOS output that sinks current to ground when LBI is below 0.625V. 4R LIM Resistor Programmable Inductor Peak Current. By connecting a resistor R LIM from this pin to ground the inductor peak current is set by IPEAK =1400/RLIM. The range for RLIM is 4.0K (for 350mA) to 1.17K (for 1.2A). 5 SHDN Shutdown Not. Tie this pin to V BATT for normal operation. Tie this pin to ground to disable all circuitry inside the chip. In shutdown the output voltage will float down to a diode drop below the battery potential. 6F B External Feedback pin. Connect this pin to GND for fixed +3.3V operation. Connect this pin to a resistor voltage divider between VOUT and GND for adjustable output operation. 7 GND Ground pin for the internal regulator bias currents. 8P GND Switch ground pin. The inductor charging current flows out of this pin. 9L X Inductor switching node. Connect one terminal of the inductor to the positive terminal of the battery. Connect the second terminal of the inductor to this pin. The inductor charging current flows into LX, through the internal charging N-channel FET, and out the GND pin. 10 V OUT Output Voltage pin. The inductor current flows out of this pin during the off-time. It is also the internal regulator voltage supply, and minimum off-time one shot input. Kelvin connect this pin to the positive terminal of the output capacitor.

Rev:001 Date:11/20/03 SP6649 Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator © Copyright 2002 Sipex Corporation ADVANCED INFORMATION THEORY OF OPERATION Detailed Desctiption: The SP6649 is a step-up DC-DC converter that starts up with input voltages as low as 0.85V (typically) and operates with input voltages down to 0.62V. The ultra low quiescent current of 12µA provides excellent efficiencies. In addi- tion to the 0.3 internal MOSFET the SP6649 has an internal synchronous rectifier eliminat- ing the need for an external diode. An internal inductive-damping switch significantly reduces inductive ringing. If the supply voltage drops below 0.62V the SP6649 goes into under volt- age lock-out opening up the internal switches. An externally programmable low battery detec- tor with open drain output provides the user the ability to monitor the supply voltage. The induc- tor peak current is externally programmable to allow for a range of inductors. Control Scheme: A minimum off-time, current limited pulse fre- quency modulation (PFM) control scheme com- bines the high output power and efficiency of a pulse width modulation (PWM) device with the ultra low quiescent current of the traditional PFM. At low to moderate output loads the PFM control provides a higher efficiencies than tradi- tional PWM converters are capable of deliver- ing. At these loads the switching frequency is determined by a minimum off-time (t OFF , MIN ) and a maximum on-time (tON , MAX ) where: tOFF K OFF / (VOUT - VBATT ) and tON K ON / VBATT with K OFF = 1.1Vµs and K ON = 3.3Vµs. BLOCK DIAGRAM VBATT SHDN VBATT VO UVLO 0.61V 0.61V SDI IBIAS VO SDI INTERNAL Vbatt FB LBI Rlim Ipkset current control current reference REF FB VO VOLOW SQ n CHARGE QR TOFF charge end IUC QKILL LX undercurrent comparator INTERNAL SUPPLY VO VBATT Max Ton VOUT QKILL PMOS NMOS LX current reference overcurrent comparator SWITCH GROUND PGND GND LBON INTERNAL GROUND LOAD Ref Block Min Toff switch buffer c c n 0.61V SP6649 c c c 1.25V c

eliminate inductive ringing. (or a minimum RLIM of 1.17K ). charge time is short-cycled. Figure 3. Inductor Current vs. Load

Rev:001 Date:11/20/03 SP6649 Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator © Copyright 2002 Sipex Corporation ADVANCED INFORMATION (ALL DIMENSIONS IN MILLIMETERS) PA CKAGE: 10-PIN MSOP 0.07 - - L ØØ1 R Seating Plane E/2 e E D Gauge Plane D A2 A b - - 1.1 0 - 0.15 Dimensions in (mm) 10-PIN MSOP JEDEC MO-187 (BA) Variation 0.75 0.85 0.95 0.17 - 0.27 0.08 - 0.23

3.00 BSC

4.90 BSC

0.4 0.60 0.80 0.95 - 0.25 - - 10 - 0.07 - - 0º 8º A b c D E L N R Ø 0º - 15ºØ1 MIN NOM MAX e

2.00 BSC

0.50 BSC

c WITH PLATING BASE METAL (b) Pin #1 indentifier must be indicated within this shaded area (D/2 * E1/2)

Rev:001 Date:11/20/03 SP6649 Ultra-low Quiescent Current, High Efficiency Boost DC-DC Regulator © Copyright 2002 Sipex Corporation ADVANCED INFORMATION Corporation SIGNAL PROCESSING EXCELLENCE Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. Sipex Corporation Headquarters and Sales Office

233 South Hillview Drive

Milpitas, CA 95035 TEL: (408) 934-7500 FAX: (408) 935-7600 Sales Office

22 Linnell Circle

Billerica, MA 01821 TEL: (978) 667-8700 FAX: (978) 670-9001 e-mail: sales@sipex.com

ORDERING INFORMATION

Part Number Operating Temperature Range Package Type