MAX17083 19-4458 Rev 0 2/09 Low-Voltage, Internal Switch, Step-Down Regulator General Description Features The MAX17083 is a fixed-frequency, current-mode, Fixed-Frequency, Current-Mode Controller step-down regulator optimized for low-voltage, low- 2.4V to 5.5V Input Range power applications. This regulator features dual internal Internal 5A Step-Down Regulator n-channel MOSFET power switches for high efficiency and reduced component count. External Schottky Internal BST Switch diodes are not required. An integrated boost switch Fault Protection: Undervoltage, Overvoltage, eliminates the need for an external boost diode. The Thermal, Peak Current Limit internal 25m low-side power MOSFET easily supports Enable Input and Power-Good Output continuous load currents up to 5A. The MAX17083 pro- duces an adjustable 0.75V to 2.7V output voltage from Voltage-Controlled Soft-Start the systems 3.3V or 5V input supply. High-Impedance Shutdown This step-down regulator uses a peak current-mode < 1A (typ) Shutdown Current control scheme to eliminate the additional external compensation required by voltage-mode architectures, Applications providing an easy-to-implement architecture without sacrificing fast transient response. The MAX17083 pro- Low-Power Architectures vides peak current-limit protection and operates in Ultra-Mobile PCs light-load pulse-skipping mode to maintain high effi- Netbook and Nettop PCs ciency under light-load conditions. Portable Gaming Independent enable input and open-drain power-good output allow flexible system power sequencing. The volt- Notebook and Subnotebook Computers age soft-start gradually ramps up the output voltage PDAs and Mobile Communicators within a predictable time period, effectively limiting the inrush current. The MAX17083 features output undervolt- age, output overvoltage, and thermal-fault protection. Ordering Information The MAX17083 is available in a 24-pin 4mm x 4mm x 0.75mm TQFN package. The exposed backside pad PART TEMP RANGE PIN-PACKAGE improves thermal characteristics. MAX17083ETG+ -40C to +85C 24 TQFN +Denotes a lead(Pb)-free/RoHS-compliant package. Pin Configuration TOP VIEW 18 17 16 15 14 13 N.C. 19 12 FB PGND 20 11 N.C. 21 10 PGND GND MAX17083 PGND GND 22 9 PGND GND 23 8 + N.C. REF 24 7 12 3 4 5 6 TQFN 4mm x 4mm Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. LX LX LX LX IN BST IN EN FREQ V CC POK SETLow-Voltage, Internal Switch, Step-Down Regulator ABSOLUTE MAXIMUM RATINGS IN to PGND...............................................................-0.3V to +6V Continuous Power Dissipation, Multilayer PCB (T = +70C) A V to GND..............................................................-0.3V to +6V 24-Pin, 4mm x 4mm TQFN CC EN to GND................................................................-0.3V to +6V (derate 27.8mW/C above +70C) ........................2222mW REF, FB, SET, FREQ, POK to GND ............-0.3V to (V + 0.3V) Operating Temperature Range ...........................-40C to +85C CC LX to GND (Notes 1, 2)................................-0.6V to (V + 0.3V) Junction Temperature......................................................+150C IN BST to GND.........................................(V - 0.3V) to (V + 6V) Storage Temperature Range .............................-65C to +150C CC LX GND to PGND (Note 2) .........................................-0.3V to +0.3V Lead Temperature (soldering, 10s) .................................+300C REF Short-Circuit Current......................................................1mA Note 1: LX has clamp diodes to PGND and IN. If continuous current is applied through these diodes, thermal limits must be observed. Note 2: Measurements valid using 20MHz bandwidth limit. 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 (Circuit of Figure 1, V = V = V = V = 5V, I = no load, T = 0C to +85C, unless otherwise noted. Typical values are at IN FREQ CC EN REF A T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS IN Input Voltage Range V 2.4 5.5 V IN V Input Voltage Range V 4.5 5.5 V CC CC IN Undervoltage Threshold No hysteresis 2.1 2.4 V Vcc Undervoltage Threshold Rising edge, 160mV hysteresis 4.2 4.5 V Shutdown Supply Current EN = GND, measured at V , T = +25C 0.1 1.0 A CC A Supply Current Regulator enabled 65 95 A REFERENCE Reference Output Voltage V No load 1.24 1.25 1.26 V REF Reference Load Regulation -1A < I < +50A 3 10 mV REF OSCILLATOR Oscillator Frequency f FREQ = GND 0.45 0.50 0.55 MHz OSC FREQ = V 1.50 CC FREQ = open 1.00 FREQ Settings MHz FREQ = REF 0.75 FREQ = GND 0.50 INTERNAL 5A STEP-DOWN CONVERTER SET = GND 0.754 0.765 0.774 SET = REF 1.107 1.122 1.136 FB Regulation Voltage V No load V FB (No Load) SET = open 1.51 1.53 1.55 SET = 5V 1.812 1.836 1.86 SET = GND 0.72 0.774 SET = REF 1.07 1.136 FB Regulation Voltage V I = 4A V FB OUT (Full Load) SET = open 1.45 1.55 SET = 5V 1.76 1.86 2 MAX17083