KIT ATION EVALU E L B A AVAIL 0µMAX 3m m 1 19-3188; Rev 1; 4/04 m x 5m 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators The MAX8516/MAX8517/MAX8518 low-dropout linear regulators operate from input voltages as low as 1.425V and are able to deliver up to 1A of continuous output current with a maximum dropout voltage of only 200mV. The output voltage can be set from 0.5V to (VIN - 0.2V) and is 1.4% accurate over load and line variations, from 0°C to +85°C. These regulators use small, 1µF ceramic input capacitors and 4.7µF ceramic output capacitors to deliver 1A output current. High bandwidth provides excellent transient response and limits the output voltage deviation to 45mV for a 20mA to 1A load step, with only a 4.7µF ceramic output capacitor, and the voltage deviations can be reduced further by increasing the output capacitor. Designed with an internal p-channel MOSFET pass transistor, the MAX8516/MAX8517/MAX8518 feature low 340µA (typ) supply current during dropout conditions. Soft-start reduces inrush current. Other features include a logic-controlled shutdown mode, short-circuit protection, and thermal-overload protection. Features ♦ 1.425V to 3.6V Input Voltage Range ♦ Guaranteed 200mV Dropout at 1A Output Current ♦ ±1.4% Output Accuracy Over Load, Line, and Temperature (0°C to +85°C), ±0.6% Initial Accuracy ♦ Compatible with Ceramic Capacitors ♦ Fast Transient Response ♦ 320µA Operating Supply Current ♦ <25µA Shutdown Supply Current ♦ Short-Circuit Protection ♦ Thermal-Overload Protection ♦ Soft-Start Limits Inrush Current The MAX8517 features a power-OK (POK) output that transitions high when the regulator output is within ±10% of its nominal output voltage. The MAX8518 features a 150ms power-on reset output. The parts are packaged in a 10-pin µMAX® package that includes an exposed pad for optimal power dispation. Ordering Information PART TEMP RANGE PIN-PACKAGE MAX8516EUB -40°C to +85°C 10 µMAX MAX8517EUB -40°C to +85°C 10 µMAX MAX8518EUB -40°C to +85°C 10 µMAX Typical Operating Circuit INPUT 1.425V TO 3.6V IN_ Post Regulators Storage Notebooks Networking PDAs Base Stations ATE OUTPUT 0.5V TO (VIN - 0.2V), 1A 1µF Applications Servers OUT_ MAX8516 MAX8517 MAX8518 POWER-ON RESET 4.7µF POR (MAX8518) FB POWER-OK POK (MAX8517) ON Optical Modules EN GND OFF µMAX is a registered trademark of Maxim Integrated Products, Inc. Pin Configurations TOP VIEW EN 1 10 N.C. IN 9 2 MAX8516 OUT EN 1 10 N.C. IN 9 2 MAX8517 OUT EN 1 IN 10 N.C. 2 MAX8518 9 OUT IN 3 8 OUT IN 3 8 OUT IN 3 8 OUT N.C. 4 7 FB POK 4 7 FB N.C. 4 7 FB N.C. 5 6 GND N.C. 5 6 GND POR 5 6 GND µMAX µMAX µMAX ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX8516/MAX8517/MAX8518 General Description MAX8516/MAX8517/MAX8518 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators ABSOLUTE MAXIMUM RATINGS IN, EN, POK (MAX8517), POR (MAX8518), FB to GND .........................................................-0.3V to +4.0V OUT to GND ..................................................-0.3V to (IN + 0.3V) Output Short-Circuit Duration.....................................Continuous Continuous Power Dissipation (TA = +70°C, EP soldered to PC board ground) 10-Pin µMAX (derate 10.3mW/°C above +70°C) .........824mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C 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. VIN = +1.8V, VOUT = +1.5V, EN = IN, IOUT = 1mA, TA = -40°C to +85°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS 3.600 V 1.38 V 3.4 V 0 +0.15 %/V 100 200 mV IN Input Voltage Range Input Undervoltage Lockout 1.425 VIN rising, 70mV hysteresis 1.32 1.35 OUT Output Voltage Range 0.5 Load Regulation IOUT = 1mA to 1A Line Regulation VIN = 1.425V to 3.6V, VOUT = 1.225V, IOUT = 1mA 0.1 Dropout Voltage (VIN - VOUT) VIN = 1.425V, IOUT = 1A, VFB = 480mV Current Limit VIN = 3.6V, VOUT = 3V, VFB = 480mV Output Shutdown Leakage VIN = 3.6V, VOUT = 0, VEN = 0 -0.15 1.6 %/A 2 2.4 A 0.25 25 µA 500 503 FB IOUT = 10mA, TA = +85°C 497 FB Threshold Accuracy VOUT = 1.225V to 3V, VIN = VOUT + 0.2V to 3.6V, IOUT = 1mA to 1A 493 FB Input Bias Current VFB = 0.5V, VIN = 3.6V 507 0.001 1 mV µA GND GND Supply Current GND Shutdown Current VIN = 3.6V, VOUT = 3V, IOUT = 100mA 320 Dropout, VIN = 3.6V, VFB = 480mV 340 600 VIN = 3.6V, EN = GND 0.25 25 µA µA POK (MAX8517 ONLY) POK Threshold VFB moving out of regulation, VHYS = 10mV, IN = 1.425V to 3.6V POK Output Voltage Low VFB = 0.4V or 0.6V, IPOK = 1mA POK Output Current High VPOK = 3.6V POK Fault Delay Time From FB to POK 2 FB high 540 550 560 FB low 440 450 460 25 mV 25 200 mV 0.001 1 µA 50 100 µs _______________________________________________________________________________________ 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators (Circuit of Figure 1. VIN = +1.8V, VOUT = +1.5V, EN = IN, IOUT = 1mA, TA = -40°C to +85°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS 440 450 460 mV 25 200 mV 0.001 1 µA 150 210 ms POR (MAX8518 ONLY) POR Reset Threshold VFB falling, VHYS = 10mV, VIN = 1.425V to 3.6V POR Output Voltage Low VFB = 0.4V or 0.6V, IPOR = 1mA POR Output Current High VPOR = 3.6V POR Rising Delay Time From FB to POR 105 EN Enable Input Threshold VIN = 1.425V to 3.6V Enable Input Bias Current VEN = 0 or 3.6V EN rising 1.2 EN falling V 0.4 -1 +1 µA THERMAL SHUTDOWN Thermal-Shutdown Threshold Output on or off TJ rising +165 TJ falling +150 °C OUTPUT TRANSIENT Load Transient IOUT = 20mA to 1A to 20mA, tRISE = tFALL = 1µs 3 % Line Transient δVIN = 0.5V, tRISE = tFALL = 5µs 3 % Note 1: Specifications to -40°C are guaranteed by design, not production tested. Note 2: Measurements at high current are pulse tested, such that the junction temperature is ambient temperature. Minimum supply voltage for output accuracy must be at least 1.425V. Typical Operating Characteristics (Circuit of Figure 1, VIN = +1.8V, VOUT = +1.5V, IOUT = 1A, COUT = 4.7µF, CIN = 1µF, TA = +25°C.) OUTPUT VOLTAGE vs. LOAD CURRENT 1.50 1.45 1.40 TA = +85°C 1.500 1.498 TA = +25°C 1.496 TA = -40°C 1.494 1.490 1.30 0 0.6 1.2 1.8 2.4 INPUT VOLTAGE (V) 3.0 3.6 ILOAD = 1A 400 300 ILOAD = 0.5A 200 ILOAD = 0A 100 1.492 1.35 500 MAX8516/17/18 toc03 1.502 GROUND CURRENT (µA) OUTPUT VOLTAGE (V) 1.55 GROUND CURRENT vs. INPUT VOLTAGE MAX8516/17/18 toc02 TA = -40°C TO +85°C OUTPUT VOLTAGE (V) 1.60 MAX8516/17/18 toc01 OUTPUT VOLTAGE vs. INPUT VOLTAGE 0 0 200 400 600 800 LOAD CURRENT (mA) 1000 1200 0 0.6 1.2 1.8 2.4 3.0 3.6 INPUT VOLTAGE (V) _______________________________________________________________________________________ 3 MAX8516/MAX8517/MAX8518 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (Circuit of Figure 1, VIN = +1.8V, VOUT = +1.5V, IOUT = 1A, COUT = 4.7µF, CIN = 1µF, TA = +25°C.) GROUND CURRENT vs. LOAD CURRENT DROPOUT VOLTAGE vs. LOAD CURRENT DROPOUT VOLTAGE (mV) TA = +85°C 350 325 TA = +25°C TA = -40°C 300 275 MAX8516/17/18 toc05 125 MAX8516/17/18 toc04 375 GROUND CURRENT (µA) 100 75 50 25 250 0 0 200 400 600 800 1000 1200 0 200 400 600 800 LOAD CURRENT (mA) LOAD CURRENT (mA) LINE INPUT TRANSIENT (VIN = +1.8V TO +2.5V, ILOAD = 1A) LOAD-TRANSIENT RESPONSE (ILOAD = 0.1A TO 1A) MAX8516/17/18 toc06 1000 MAX8516/17/18 toc07 VOUT AC-COUPLED 20mV/div VOUT AC-COUPLED 50mV/div VIN AC-COUPLED 0.5V/div ILOAD 1A/div CIN = 220µF ELECTROLYTIC CAP CLOSE TO IN 100µs/div 40µs/div PSRR vs. FREQUENCY (MAX8516) SHUTDOWN RESPONSE MAX8516/17/18 toc08 MAX8516/17/18 toc09 80 70 60 VOUT 1V/div IIN 1A/div 50 PSRR (dB) MAX8516/MAX8517/MAX8518 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators 40 30 20 10 EN 2V/div 100µs/div 0 ILOAD = 100mA 0.01 0.1 1 10 100 FREQUENCY (kHz) 4 _______________________________________________________________________________________ 1000 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators FB VOLTAGE vs. TEMPERATURE OUTPUT RIPPLE VOLTAGE MAX8516/17/18 toc11 MAX8516/17/18 toc10 502 FB VOLTAGE (mV) 501 VOUT AC-COUPLED 1mV/div 500 499 ILOAD = 10mA 498 -40 -15 10 35 60 85 100µs/div TEMPERATURE (°C) OVERCURRENT THRESHOLD vs. TEMPERATURE SHORT-CIRCUIT CURRENT MAX8516/17/18 toc13 MAX8516/17/18 toc12 1.90 VOUT 1V/div 1.85 IOUT 2A/div 1.80 1.75 -40 -15 10 35 100µs/div 85 60 TEMPERATURE (°C) 75 MAX8516/17/18 toc14 CASE TEMPERATURE vs. LOAD CURRENT CASE TEMPERATURE (°C) OVERCURRENT THRESHOLD (A) 1.95 VIN = 2.5V; TA = +25°C 60 45 30 15 0 0 200 400 600 800 1000 LOAD CURRENT (mA) _______________________________________________________________________________________ 5 MAX8516/MAX8517/MAX8518 Typical Operating Characteristics (continued) (Circuit of Figure 1, VIN = +1.8V, VOUT = +1.5V, IOUT = 1A, COUT = 4.7µF, CIN = 1µF, TA = +25°C.) 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators MAX8516/MAX8517/MAX8518 Pin Description PIN NAME DESCRIPTION MAX8516 MAX8517 MAX8518 1 1 1 EN Enable Input. Set low to place the device in low-current shutdown mode. Set high for normal operation. 2, 3 2, 3 2, 3 IN Regulator Input. VIN can range from +1.425V to +3.6V. Bypass with a 1µF or higher ceramic capacitor to GND. 4, 5, 10 5, 10 4, 10 N.C. No Connection. Pin 10 is internally pulled down to GND with a 10kΩ resistor. Leave floating. 6 6 6 GND 7 7 7 FB Feedback Pin. Connect to output through a voltage-divider to set the output. 8, 9 8, 9 8, 9 OUT Regulator Output. Bypass with a 4.7µF ceramic capacitor to GND (a smaller capacitor can be used if maximum load is less than 1A, i.e., COUT = IOUT (max) ✕ (1µF/200mA). — 4 — POK Power-OK Output (MAX8517 Only). Open-drain output. Connect to a positive supply with a pullup resistor. If not used, leave pin unconnected. See the Detailed Description. — — 5 POR Power-On Reset Output. Open-drain output. Connect to a positive supply with a pullup resistor. If not used, leave pin unconnected (see the Detailed Description for more details). GND Exposed Pad on the Underside of the Package. Solder to the ground plane for proper heat dissipation. EP Ground Functional Diagram IN THRESHOLD OVERTHERMAL PROTECTION REF EN OVERTHERMAL PROTECTION 0.50V 0.55V 0.45V UNDERVOLTAGE LOCKOUT ERROR AMP WITH SOFT-START MOS DRIVER WITH ILIMIT OUT FB MAX8516 MAX8517 MAX8518 POK (MAX8517 ONLY) POR (MAX8518 ONLY) GND 6 _______________________________________________________________________________________ 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators The MAX8516/MAX8517/MAX8518 are low-input, lowdropout, PMOS regulators capable of delivering up to 1A of output current with as little as 200mV of headroom from input to output. The PMOS output stage can be driven from input voltages down to +1.425V without sacrificing stability or transient performance. Since these regulators have a PMOS output device, supply current is not a significant function of load or input headroom. Internal P-Channel Pass Transistor The MAX8516/MAX8517/MAX8518 feature a 100mΩ (typ) p-channel MOSFET pass transistor. Unlike similar designs using PNP pass transistors, p-channel MOSFETs require no base drive, which reduces quiescent current. PNP-based regulators also waste considerable current in dropout when the pass transistor saturates and use high base-drive currents under large loads. The MAX8516/ MAX8517/MAX8518 do not suffer from these problems and consume only 340µA (typ) of quiescent current under heavy loads, as well as in dropout. Short-Circuit/Thermal Fault Protection The MAX8516/MAX8517/MAX8518 are fully protected from a short circuit at the output through current-limiting and thermal-overload circuitry. In the fault condition when the output is shorted to ground, the output current is limited to 2A. Under these conditions, the part quickly heats up. When the junction temperature reaches +165°C, the thermal-overload circuitry turns off the output, allowing the part to cool down. When the junction temperature cools to +150°C, the output turns back on and tries to reestablish regulation. Current limiting and thermal protection continue until the fault is removed. For continuous operation, do not exceed the absolute maximum junction-temperature rating of TJ = +150°C. ADJUSTABLE OUTPUT +1.425V TO +3.6V IN OUT 1µF IN MAX8516 MAX8517 MAX8518 OUT R1 100kΩ* FB POK (MAX8517) OR POR (MAX8518) R2 ENABLE EN SHUTDOWN *FOR MAX8517 AND MAX8518 GND 4.7µF Output Voltage Selection The MAX8516/MAX8517/MAX8518 feature an adjustable output voltage from 0.5V to 3.4V, using two external resistors connected as a voltage-divider to FB as shown in Figure 1. The output voltage is set by the following equation: R1 ⎞ ⎛ VOUT = VFB ⎜1 + ⎟ ⎝ R2 ⎠ where typically VFB = 0.5V. Choose R2 ≤ 5kΩ to optimize quiescent current, accuracy, and high-frequency power-supply rejection. To simplify resistor selection: ⎛V R1 = R2 ⎜ OUT ⎝ VFB − ⎞ 1⎟ ⎠ Soft-Start Inherent soft-start limits inrush current. Peak inrush current is dependent on the value of COUT and can be calculated as follows: ⎛C (µF) ⎞ IINRUSH = ILOAD + ⎜ OUT ⎟ 66 ⎝ ⎠ Shutdown Mode The MAX8516/MAX8517/MAX8518 include an enable input. To shut down the device, pull EN to GND. For normal operation, connect the EN to IN. During shutdown, an internal 10kΩ resistor pulls down the output. Power-OK (MAX8517 Only) The MAX8517 features a power-OK (POK) output to indicate the status of the output. POK remains high when the regulator output is within ±10% of its nominal output voltage. If the output voltage falls or rises outside this range, POK transitions low. This open-drain output requires an external pullup resistor to IN. An internal delay circuit prevents POK from switching for 50µs (typ) after the trip threshold is initially reached. If the part is in shutdown mode, POK is low. Power-On Reset (MAX8518 Only) The MAX8518 features a power-on reset (POR) output that transitions high 140ms (typ) after the output has risen above 90% of its final value. This open-drain output requires an external pullup resistor to IN. If the part is in shutdown mode, falls below 90% of the nominal output voltage, or experiences a short-circuit or thermal fault, POR immediately transitions low. Figure 1. Typical Application Circuit _______________________________________________________________________________________ 7 MAX8516/MAX8517/MAX8518 Detailed Description MAX8516/MAX8517/MAX8518 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators Operating Region and Power Dissipation Noise, PSRR, and Transient Response The maximum power dissipation depends on the thermal resistance of the IC package and circuit board, the temperature difference between the die junction and ambient air, and the rate of airflow. The power dissipated in the device is P = IOUT ✕ (VIN - VOUT). The package features an exposed thermal pad on its underside. This pad lowers the thermal resistance of the package by providing a direct heat conduction path from the die to the PC board. The MAX8516/MAX8517/MAX8518 are designed to operate with low dropout voltages and low quiescent currents while still maintaining good noise, transient response, and AC rejection (see the Typical Operating Characteristics for a plot of Power-Supply Rejection Ratio (PSRR) vs. Frequency). When operating from noisy sources, improved supply-noise rejection and transient response can be achieved by increasing the values of the input and output bypass capacitors and through passive filtering techniques. The MAX8516/ MAX8517/MAX8518 load-transient response graphs (see the Typical Operating Characteristics) show two components of the output response: a DC shift from the output impedance due to the load current change, and the transient response. A typical transient overshoot for a step change in the load current from 20mA to 1A is 45mV. Use larger output ceramic capacitors greater than 4.7µF up to 50µF to attenuate the overshoot. Additionally, the ground pins (GND) perform the dual function of providing an electrical connection to system ground and channeling heat away. Connect the exposed backside pad and GND to the system ground using a large pad or ground plane, or multiple vias to the ground plane layer. Applications Information Capacitor Selection and Regulator Stability Capacitors are required at the MAX8516/MAX8517/ MAX8518 inputs and outputs for stable operation over the full temperature range and with load currents up to 1A. Connect a 1µF capacitor between IN and ground and a 4.7µF capacitor with low equivalent series resistance (ESR) between OUT and ground for 1A output current. The input capacitor (CIN) lowers the source impedance of the input supply. If input-supply source impedance is high, place a larger input capacitor close to IN to prevent VIN sagging due to load transients. Smaller output capacitors can be used for output currents less than 1A. Calculate COUT as follows: Chip Information TRANSISTOR COUNT: 2849 PROCESS: BiCMOS COUT = IOUT(MAX) × (1µF / 200mA) 8 _______________________________________________________________________________________ 1.425V to 3.6V Input, 1A, 0.2V Dropout LDO Regulators 10L UMAX, EXPPADS.EPS PACKAGE OUTLINE, 10L uMAX, EXPOSED PAD 21-0109 C 1 1 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 9 © 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX8516/MAX8517/MAX8518 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)