MAX1672 19-1307 Rev 2 11/02 Step-Up/Down DC-DC Converter in QSOP Package General Description Features The MAX1672 integrates a step-up DC-DC converter with a Step-Up/Down Voltage Conversion linear regulator to provide step-up/down voltage conver- 1.8V to 11V Input Range sion. This device provides a constant output voltage for 3.3V/5V or Adjustable Output Voltage Range inputs that vary above and below the output voltage. It has a 1.8V to 11V input range and a preset 3.3V or 5V output. Output Current: The output can also be set from 1.25V to 5.5V using two 300mA at 5V (V 2.5V) IN resistors. Typical efficiency is 85%. 150mA at 5V (V 1.8V) IN The MAX1672s step-up/linear-regulator configuration per- Smaller Inductor than SEPIC and Flybacks mits the use of a single, physically smaller inductor than Load Disconnects from Input in Shutdown can be used with competing SEPIC and flyback configura- Supply Current from Battery: tions. Switch current is also selectable, permitting the use 85A (No-Load) of smaller inductors in low-current applications. The linear 0.1A (Shutdown) regulator also acts as a filter to reduce output ripple voltage. PGI/PGO Low-Battery Comparator The MAX1672 has a low 85A quiescent supply current, which is further reduced to 0.1A in logic-controlled shutdown. The 16-Pin QSOP Package output voltage is disconnected from the input in shutdown. (Same Footprint as 8-pin SO) The MAX1672 also has a PGI/PGO low-battery detector. No External FETs Required The MAX1672 comes in a 16-pin QSOP package (same size Thermal and Short-Circuit Protection as a standard 8-pin SO). For a larger device that delivers more output current, refer to the MAX710/MAX711. The preassem- bled MAX1672 evaluation kit is available to speed designs. Applications Ordering Information Single-Cell, Lithium-Powered 2-Cell to 4-Cell AA Alkaline PART TEMP RANGE PIN-PACKAGE Portable Devices Hand-Held Equipment MAX1672C/D 0C to +70C Dice* 3.3V and Other Low-Voltage Battery-Powered Devices MAX1672EEE -40C to +85C 16 QSOP Systems with AC Input Adapters *Dice are tested at T = +25C. A Digital Cameras Typical Operating Circuit Pin Configuration INPUT 1.8V TO 11V TOP VIEW IN LX PGI PS LX 1 16 LX PGND 2 15 PGND MAX1672 ONB 3 14 GND 3.3V/5V ON OFF ONA OUT ONA 4 MAX1672 13 REF OUTPUT ON OFF ONB 3/5 5 12 IN 3.3V 5V 3/5 PGI 6 11 PS 0.5A 0.8A ILIM PG0 LOW-BATTERY PGO 7 10 FB DETECTOR REF FB OUTPUT ILIM 8 9 OUT PGND GND QSOP 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 MANUAL FOLLOWS DATA SHEETStep-Up/Down DC-DC Converter in QSOP Package ABSOLUTE MAXIMUM RATINGS Continuous Power Dissipation (T = +70C) IN, PS, LX, OUT, PGO to GND ......................... -0.3V to +11.5V A 16-Pin QSOP (derate above +70C by 8.3mW/C).......667mW ILIM, ONA, ONB, FB, 3/5, REF, PGI to GND......................................-0.3V to (V + 0.3V) Operating Temperature Range ......................... -40C to +85C PS Junction Temperature .................................................... +150C PGND to GND .......................................................-0.3V to +0.3V OUT Short Circuit to GND ..........................................Continuous Storage Temperature Range ........................... -65C to +160C Lead Temperature (soldering, 10s) ................................ +300C Output Current ..................................................................350mA 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 = 6V, C = 0.1F, C = 4.7F, T = -40C to +85C, unless otherwise noted. Typical values are at T = +25C.) (Note 1) REF OUT A A PS PARAMETER CONDITIONS MIN TYP MAX UNITS Input Voltage 1.8 11.0 V Startup Voltage 0.9 V T = 0C to +85C 4.8 5.2 A 3/5 = GND FB = GND, V = 6.8V PS T = -40C to +85C 4.75 5.00 5.25 A Output Voltage I = 0mA to V OUT T = 0C to +85C 3.17 3.43 A 150mA 3/5 = PS T = -40C to +85C 3.13 3.30 3.47 A Output Voltage Adjustment 1.25 5.5 V Range Output Load Regulation V = 2V, 3/5 = GND, FB = GND, I = 10mA to 150mA 0.003 %/mA IN OUT Output Line Regulation V = 3V to 5V, 3/5 = GND, I = 100mA 0.15 %/V IN OUT ONA = PS or ONB = GND, current measured into PS pin, Quiescent Current 85 125 A I = 0mA OUT Shutdown Quiescent Current 0.1 1 A ONA = GND, ONB = PS, current measured into PS pin Reference Voltage I = 0mA 1.21 1.25 1.29 V REF T = 0C to +85C 1.21 1.25 1.29 A FB Voltage OUT = FB V T = -40C to +85C 1.20 1.30 A FB Dual-Mode Trip Threshold Hysteresis = 15mV typical 70 mV FB Input Current V = 1.3V 150 nA FB IN Input Current V = GND to 11V 36 A IN V = 5.5V, I = 50mA 0.6 1.3 PS LX LX On-Resistance V = 2.7V, I = 50mA 0.9 2.0 PS LX LX Leakage Current V = 11V, ONA = GND, ONB = PS 0.1 1 A LX T = 0C to +85C 0.35 0.5 0.65 A ILIM = GND T = -40C to +85C 0.3 0.5 0.7 A LX Current Limit A T = 0C to +85C 0.6 0.8 1.0 A ILIM = PS T = -40C to +85C 0.5 0.8 1.1 A V = 5.5V, I = 50mA 1.2 2.4 PS OUT Output PFET Resistance V = 2.7V, I = 50mA 2.3 4.6 PS OUT Output PFET Leakage Current 0.1 1 A V = 0V, ONA = GND, ONB = PS OUT Output PFET Current Limit V = 5.5V 0.35 0.7 1.4 A PS 2 MAX1672