A8181SLB

8181 LOW-DROPOUT, 5 V REGULATOR 8181 LOW-DROPOUT, 5 V REGULATOR — HIGH EFFICIENCY Especially suited for hand-held, portable, battery-operated equipment such as cellular telephones, the A8181SLB low dropout voltage regulator provides high efficiency for maximum battery life in a minimum package size. Equally applicable to camcorders and portable computers, the device provides a fixed 5 V regulated continuous output at almost 200 mA of load current under worst-case conditions. Under normal operating conditions, output currents over 500 mA are permitted. A MOSFET pass element delivers high output current with an input-output differential of less than 300 mV. For high efficiency, the low dropout voltage allows a longer battery discharge before output voltage regulation is lost. A low quiescent current, even during high load conditions, makes the device ideal for standby power systems. High regulator accuracy and excellent temperature characteristics are provided by a bandgap reference. An enable input gives the designer complete control over sequential power-up or emergency shutdown. This device is supplied in a 16-lead wide-body, small-outline plastic power package (SOIC) for surface-mount applications. The copper batwing provides for maximum package power dissipation in the smallest possible construction. The A8181SLB is rated for operation over a temperature range of -20°C to +85°C. Data Sheet 27468* GROUND GROUND ENABLE ABSOLUTE MAXIMUM RATINGS at TA = +25°C Input Voltage, VI ................................... 10 V Output Current, IO (40% duty cycle) ............................ 1 A* (75% duty cycle) ..................... 500 mA* (continuous) ............................ 370 mA* Operating Temperature Range, TA ................................. -20°C to +85°C Junction Temperature, TJ .............. +150°C† Storage Temperature Range, TS ............................... -40°C to +150°C * Output current rating is limited by input voltage, duty cycle, and ambient temperature. Under any set of conditions, do not exceed a junction temperature of +150°C. See next page. † Fault conditions that produce excessive junction temperature will activate device thermal shutdown circuitry. These conditions can be tolerated but should be avoided. T C UY DL ON RO PE DC EN UE IN ER TF NE OR CR IS O DF — NC NC NC 1 2 3 4 5 16 15 14 13 12 11 10 9 OUT OUT NC 5V GROUND GROUND NC NC NC 6 7 VR IN IN 8 Dwg. PS-018 FEATURES AND BENEFITS s s s s s High Efficiency Provides Extended Battery Life Less Than 300 mV Dropout Voltage Low Quiescent Current >200 mA Output Current LSTTL-Compatible ON/OFF Control For Sequential Power-up or Emergency Shutdown s Internal Thermal Protection s SOIC Surface-Mount Package Always order by complete part number: A8181SLB . 8181 LOW-DROPOUT, 5 V REGULATOR FUNCTIONAL BLOCK DIAGRAM IN IN 7 8 15 16 OUT OUT BIAS DRIVE ERROR AMP ENABLE 6 THERMAL PROTECT. ENABLE BANDGAP REF. 12-13 4-5 Dwg. FS-012 MAXIMUM ALLOWABLE OUTPUT CURRENT with device mounted on 2.24" x 2.24" (56.9 mm x 56.9 mm) solder-coated copper-clad board in still air. Maximum Allowable Output Current in Milliamperes with VI = 10 V, TJ = 150°C* dc (Duty Cycle) TA 25°C 50°C 70°C 85°C 100% 370 295 235 190 90% 415 330 265 215 80% 465 370 295 240 70% 530 425 340 275 60% 620 495 395 320 50% 745 595 475 385 40% 930 745 595 485 30% 1000 995 795 645 20% 1000 1000 1000 970 * IO = (TJ - TA)/([VI - VO] RθJA • dc) = (150 - TA)/(5 • 67 • dc) Output current rating can be increased (to 1 A maximum) by heat sinking or reducing the input voltage. With an infinite heat sink, R-JA = R-JT = 6°C/W. Conditions that produce excessive junction temperature will activate device thermal shutdown circuitry. These conditions can be tolerated but should be avoided. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 W Copyright © 1992, 1995 Allegro MicroSystems, Inc. 8181 LOW-DROPOUT, 5 V REGULATOR ELECTRICAL CHARACTERISTICS at TA +25°C (unless otherwise noted). Limits Characteristic Output Voltage Symbol VO Test Conditions TA = 25°C, 5.5 V ≤ VI ≤ 10 V, 0 mA ≤ IO ≤ 500 mA† TA = 85°C, 5.5 V ≤ VI ≤ 10 V, 0 mA ≤ IO ≤ 500 mA*† Output Volt. Temp. Coeff. Line Regulation Load Regulation Dropout Voltage Quiescent Current (GND terminal current) αVO ∆VO(∆VI) ∆VO(∆IO) VImin - VO IQ IO = 0 5.5 V ≤ VI ≤ 10 V, Output open 0 mA ≤ IO ≤ 500 mA†, VI = 6 V IO = 500 mA† VI = 10 V, IO = 500 mA† VI = 10 V, Output open IQ(off) ENABLE Input Voltage VEH VEL ENABLE Input Current Thermal Shutdown Temp. Thermal Resistance IE TJ RθJA RθJT Typical values are given for circuit design information only. * This parameter is tested to a lot sample plan only. † Pulse test (