MAX8627 19-3995 Rev 0 3/06 Low V , 20A IQ, 1MHz Synchronous BATT Boost Converter with True Shutdown General Description Features The MAX8627 step-up converter is a high-efficiency, 1MHz PWM Switching Frequency low-quiescent current, synchronous boost converter True Shutdown Output with True Shutdown and inrush current limiting. The MAX8627 generates any boosted output voltage from Up to 95% Efficiency 3V to 5V from either a 2-cell NiMH/NiCd or a single-cell 1.0A Guaranteed Output Current Li+/Li polymer battery. Quiescent current is only 20A (typ), and at light loads Soft-Start Eliminates Inrush Current the converter pulses only as needed for best efficiency. 20A (typ) Quiescent Current At higher loads, PWM mode maintains fixed 1MHz operation for lowest noise and ripple. 0.1A Logic-Controlled Shutdown The MAX8627 includes an internal soft-start to limit Internal Synchronous Rectifier inrush current to a maximum of 500mA. Additional fea- Internal Compensation tures include True Shutdown, internal compensation, and adjustable current limit. The MAX8627 is available Adjustable Current Limit in a tiny 3mm x 3mm TDFN package and is ideal for Low-Noise Antiringing Feature use in handheld devices such as DSCs, PDAs, and smartphones. Tiny 14-Pin, 3mm x 3mm, TDFN Package Applications DSC Motors and Backup Power Ordering Information Microprocessor/DSP Core Power PIN- PKG TOP Cellphones, PDAs, MP3 Players PART PACKAGE CODE MARK Portable Handheld Devices 14 TDFN-EP* MAX8627ETD+ T1433-2 AAQ 3mm x 3mm Note: The device operates in the -40C to +85C extended oper- ating temperature range. True Shutdown is a trademark of Maxim Integrated Products, Inc. *EP = Exposed pad. +Denotes lead-free package. Typical Operating Circuit Pin Configuration INPUT BATTERY TOP VIEW 2.5V TO 4.2V L1 C1 C2 14 13 12 11 10 9 8 4, 5 8, 9 OUTPUT LX BATT 3V TO 5V ON C3 C4 6,7 UP TO 1A 3 POUT OFF ON MAX8627 14 12 R1 MAX8627ETD+ AGND OUTS R4 2 13 ILIM FB + R3 1243 5 6 7 R2 1 10, 11 GND PGND TDFN 3mm x 3mm Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE GND OUTS FB ILIM ON AGND BATT PG BATT PG POUT LX POUT LXLow V , 20A IQ, 1MHz Synchronous BATT Boost Converter with True Shutdown ABSOLUTE MAXIMUM RATINGS OUTS, BATT to GND ................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A LX Current (Note 1)...............................................................3.5A 14-Pin TDFN 3mm x 3mm AGND, PG to GND ................................................-0.3V to +0.3V (derate 18.2mW/C above +70C).............................1454mW POUT to OUTS ......................................................-0.3V to +0.3V Operating Temperature Range ...........................-40C to +85C FB, ILIM, ON to Junction Temperature......................................................+150C GND.....0.3V to the higher of (V + 0.3V) and (V + 0.3V) Storage Temperature Range .............................-65C to +150C OUTS BATT Lead Temperature (soldering, 10s) .................................+300C Note 1: LX has internal clamp diodes to the IC internal power node V (where V is the higher of BATT or POUT) and PG. PWR PWR Applications that forward bias these diodes should take care not to exceed the devices power-dissipation limits. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = V = 5V, V = V = 3.6V, V = GND, T = -40C to +85C, typical values are at T = +25C, unless otherwise OUTS POUT ON BATT ILIM A A noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS GENERAL Operating Input Voltage Range (Note 1) 0.9 5.5 V Minimum Startup Voltage No load (Note 1) 1.2 1.5 V Maximum Startup Current Limit 0.5 A T = +25C 0.1 1 A Shutdown, ON = GND T = +85C 0.2 A Supply Current T = 0C to +85C2030 A A No load, no switching T = -40C (Note 2) 20 35 A No load, switching 20 OSCILLATOR Switching Frequency 0.95 1.0 1.05 MHz Startup Switching Frequency 2.0 MHz Maximum Duty Cycle 82.5 87.0 % Output Voltage Adjust Range 3.0 5.2 V FB Regulation Voltage No load 1.005 1.015 1.025 V FB Load Regulation 0A to 1A output current load step -30 mV/A FB Line Regulation V = 2.7V to 3V, output current = 0.5A +20 mV BATT T = +25C -50 -10 +50 V = 1.2V, A FB FB Input Leakage Current nA V = V = V = 5.5V OUTS POUT BATT T = +85C -10 A Low level 0.25 ILIM Dual Mode Threshold V High level 0.45 Idle Mode Trip Level (Note 3) 50 mA DC-DC SWITCHES n-Channel On-Resistance 0.15 0.25 p-Channel On-Resistance 0.15 0.25 Damping Switch On-Resistance 17 30 V = 0V 3.2 3.5 3.7 ILIM n-Channel Current limit A V = 0.6V 1.0 ILIM Dual Mode is a trademark of Maxim Integrated Products, Inc. 2 MAX8627