MAX8718/MAX8719 19-3495 Rev 0 11/04 High-Voltage, Low-Power Linear Regulators for Notebook Computers General Description Features The MAX8718/MAX8719 are micropower, 8-pin TDFN 4V to 28V Input Range linear regulators that supply always-on, keep-alive 18A Quiescent Supply Current power to CMOS RAM, real-time clocks (RTC), and microcontrollers in systems with high-voltage batteries. <3A Shutdown Supply Current The circuits consist of a 100mA linear regulator and a 100mA Output Current power-good comparator (PGOOD) with fixed-output delay. Key features include wide input voltage range, 3.3V or 5V, Pin-Selectable Output (MAX8718) low-dropout voltage, and low-quiescent supply current. Adjustable 1.24V to 28V Output (MAX8719) Despite a miserly 25A (max) no-load quiescent cur- rent, the MAX8718/MAX8719 have good line- and load- 2% Output Accuracy transient response and excellent AC power-supply Thermal-Overload Protection rejection. They provide a clean fixed 5V or 3.3V output (MAX8718), or an adjustable 1.24V to 28V output Delayed Power-Good Output (MAX8719), even when subjected to fast supply-volt- Thermally Enhanced 8-Pin TDFN Package age changes that occur during the switchover from bat- tery to AC-adapter input power. The space-saving TDFN package has excellent thermal characteristics and tolerates up to 1951mW of power dissipation. Internal foldback current limiting and thermal shutdown Ordering Information protect the regulator from overload and thermal faults. OUTPUT In addition to the main notebook-computer application, PART TEMP RANGE PIN-PACKAGE VOLTAGE these devices are useful in other low-power, high-volt- age applications (4V < V < 28V) such as smart batter- IN 8 TDFN 3mm x MAX8718ETA -40C to +85C 3.3V/5V ies, current control loops, telecom emergency power, 3mm and housekeeping power for off-line supplies. 8 TDFN 3mm x MAX8719ETA -40C to +85C Adjustable The MAX8718/MAX8719 are available in a thermally 3mm enhanced 3mm x 3mm, 8-lead TDFN package. Applications Pin Configuration CMOS/RTC Backup Power Microcontroller Power TOP VIEW Notebook Computers Smart-Battery Packs 1 8 IN OUT PDAs and Handy-Terminals GND 2 7 I.C. MAX8718 5/3 (FB) 3 MAX8719 6 SHDN Battery-Powered Systems V 4 5 PGOOD CC TDFN 3mm 3mm () ARE FOR THE MAX8719. 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.High-Voltage, Low-Power Linear Regulators for Notebook Computers ABSOLUTE MAXIMUM RATINGS IN to GND...............................................................-0.3V to +30V I.C. to GND...............................................................-0.3V to +6V SHDN to GND ..............................................-0.3V to (V + 0.3V) OUT Short Circuit to GND.......................................................30s IN 5/3 (MAX8718) to GND.............................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A FB (MAX8719) to GND .............................................-0.3V to +6V 8-Pin TDFN (derate 24.4mW/C above +70C) ..........1951mW OUT (MAX8718) to GND ..........................................-0.3V to +6V Operating Temperature Range ...........................-40C to +85C OUT (MAX8719) to GND ........................................-0.3V to +30V Junction Temperature......................................................+150C V to GND (MAX8718)...........................................-0.3V to +6V Storage Temperature Range .............................-65C to +150C CC V to GND (MAX8719)........................................-0.3V to +2.7V Lead Temperature (soldering, 10s) .................................+300C CC PGOOD to GND .....................................................-0.3V to +30V 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 = 15V, I = 5A, T = 0C to +85C. Typical values are at T = +25C, unless otherwise noted.) (Note 1) IN OUT A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Voltage Range V 428V IN SHDN = IN, T = +25C1218s A Supply Current (MAX8718) I IN SHDN = IN, V = 6V to 28V 25 A IN 0V < V < 2.7V, T = +25C -0.1 +0.1 CC A V Input Current (MAX8719) A CC 0V < V < 2.7V, T = 0C to +85C 0.04 CC A 0V < V < 5.5V, T = +25C 3.4 CC A V Input Current (MAX8718) A CC 0V < V < 5.5V, T = 0C to +85C 2.3 CC A OUT Minimum Load Current 5A Shutdown Supply Current SHDN = 0V 1.2 3 A Dropout Supply Current V set to 5V, V = 4.7V 85 A OUT IN V = 6V to 28V, I = 1mA, 5/3 = GND, IN LOAD 3.26 3.33 3.40 T = +25C A V = 6V to 28V, I = 1mA, 5/3 = OUT, IN LOAD 4.95 5.05 5.15 T = +25C A OUT Output Voltage (MAX8718) V V = 6V to 28V, I = 5A to 100mA, IN LOAD 3.15 3.48 5/3 = GND V = 6V to 28V, I = 5A to 100mA, IN LOAD 4.75 5.25 5/3 = OUT FB = OUT, V = 6V to 28V, I = 1mA 1.215 1.240 1.265 IN LOAD FB Threshold (MAX8719) V V FB FB = OUT, V = 6V to 28V, IN 1.18 1.28 I = 5A to 100mA (Note 2) LOAD V = 1.3V, T = +25C -30 +30 FB A FB Input Current (MAX8719) I nA FB V = 1.3V, T = 0C to +85C15 FB A V = 5V, T = +25C -30 +30 5/3 A 5/3 Input Current (MAX8718) I nA 5/3 V = 5V, T = 0C to +85C2 5/3 A Dropout Voltage V I = 100mA (Note 3) 560 mV DROPOUT LOAD 2 MAX8718/MAX8719