19-4586; Rev 1; 2/11 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input Features The MAX15029/MAX15030 low-dropout linear regulators operate from input voltages as low as 1.425V and deliver up to 500mA of continuous output current with a typical dropout voltage of only 40mV. The output voltage is adjustable from 0.5V to VIN and is ±2% accurate over load and line variations, from -40°C to +125°C. The MAX15030 features a BIAS input of 3V to 5.5V from an always-on power supply. The BIAS input current is reduced down to less than 2µA during the shutdown. These regulators use small, 1µF ceramic input capacitors and 2.2µF ceramic output capacitors to deliver 500mA output current. High bandwidth provides excellent transient response and limits the output voltage deviation to 10mV for a 100mA to 500mA load step, with only a 2.2µF ceramic output capacitor, and the voltage deviations can be reduced further by increasing the output capacitor. ♦ 1.425V to 3.6V Input Voltage Range These devices offer a logic-controlled shutdown input to reduce input current (IIN) consumption down to less than 5.5µA in standby mode. Other features include a soft-start to reduce inrush current, short-circuit protection, and thermal-overload protection. ♦ Thermally Enhanced 3mm x 3mm TDFN Package The MAX15030 features a BIAS input allowing a secondary supply to keep the LDO’s internal circuitry alive if the voltage on IN goes to 0. Both devices are fully specified from -40°C to +125°C and are available in a 10-pin thermally enhanced TDFN package (3mm x 3mm) that includes an exposed pad for optimal power dissipation. For a 1A version of these LDOs, refer to the MAX15027/MAX15028 data sheet. ♦ Output Voltage Programmable from 0.5V to VIN ♦ Guaranteed Maximum 150mV Dropout at 500mA Output Current ♦ 2% Output Accuracy Over Load, Line, and Temperature ♦ Stable with Ceramic Capacitors ♦ Fast Transient Response ♦ 60µA Operating Bias Supply Current ♦ 1.2µA Shutdown Bias Supply Current ♦ Short-Circuit and Thermal Protection ♦ -40°C to +125°C Operating Temperature Range ♦ Soft-Start Limits Inrush Current Ordering Information PART PINPACKAGE TEMP RANGE TOP MARK MAX15029ATB+ -40°C to +125°C 10 TDFN-EP* +AUF MAX15029ATB/V+ -40°C to +125°C 10 TDFN-EP* +AXK MAX15030ATB+ -40°C to +125°C 10 TDFN-EP* +AUG /V denotes an automotive qualified part. +Denotes a lead(Pb)-free/RoHS-compliant package. For tape-and-reel orders, add a “T” after the “+.” *EP = Exposed pad. Applications Pin Configurations Automotive (Dead-Man LDO) Servers TOP VIEW Storage Networking IN 1 IN 2 IN 3 I.C. 4 + 10 OUT 9 OUT 8 GND 7 FB 6 SS Base Stations Optical Modules ATE EN Typical Operating Circuits appear at end of data sheet. 5 MAX15029 EP TDFN (3mm x 3mm) Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX15029/MAX15030 General Description MAX15029/MAX15030 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input ABSOLUTE MAXIMUM RATINGS IN, FB, SS, I.C. to GND..........................................-0.3V to +4.0V BIAS to GND.............................................................-0.3V to +6V EN to GND ................-0.3V to the lower of (VBIAS + 0.3V) or +6V OUT to GND ................................................-0.3V to (VIN + 0.3V) Output Short-Circuit Duration.....................................Continuous Continuous Power Dissipation (TA = +70°C) TDFN (derate 24.4mW/°C above +70°C)....................1951mW Operating Junction Temperature Range ...........-40°C to +125°C Maximum Junction Temperature .....................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Soldering Temperature (reflow) .......................................+260°C PACKAGE THERMAL CHARACTERISTICS (Note 1) TDFN Junction-to-Ambient Thermal Resistance (θJA) ............41°C/W Junction-to-Case Thermal Resistance (θJC) ...................9°C/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. 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 = 1.2V, EN = IN for MAX15029, EN = BIAS for MAX15030, IOUT = 100mA, TA = TJ = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS IN MAX15029 Input Voltage Range Undervoltage Lockout Undervoltage Lockout Hysteresis VIN VUVLO MAX15030 VIN rising 1.425 VBIAS = 3V to 5.5V 1.425 3.600 BIAS = IN 3.000 3.600 MAX15029 1.275 1.325 1.375 MAX15030 1.04 1.09 1.14 VUVLO_HYST I OUT = 2mA Quiescent GND Current I GND Input Supply Current in Shutdown I IN_SD 3.600 50 V V mV VIN = 1.425V to 3.6V, VOUT = 1.2V, I OUT = 1mA, VBIAS = 3.3V 160 275 410 VIN = 3.6V, VOUT = 3.3V, I OUT = 100mA 180 325 560 VIN = 3.3V, VOUT = 3.3V, I OUT = 500mA 170 315 470 0.1 5.5 5.5 V 2.5 2.7 V VEN = 0V (TA = -40°C to +85°C) μA μA BIAS (MAX15030) Input Voltage Range Undervoltage Lockout VBIAS Undervoltage Lockout Hysteresis Quiescent Input Supply Current Input Supply Current in Shutdown 2 3 VBIAS_UVLO VBIAS rising 2.3 IOUT = 2mA IBIAS IBIAS_SD 110 VEN = VBIAS EN = GND 20 mV 60 120 VIN = 0V, VOUT = 0V, VBIAS = 3.3V 1.2 2 VIN = 3.3V, VOUT = 0V, VBIAS = 3.3V 1.2 2 VIN = 3.3V, VOUT = 0V, VBIAS = 5V 1.5 3 _______________________________________________________________________________________ μA μA 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input (Circuit of Figure 1; VIN = 1.8V, VOUT = 1.2V, EN = IN for MAX15029, EN = BIAS for MAX15030, IOUT = 100mA, TA = TJ = -40°C to +125°C. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUT Output Voltage Range VOUT 0.5 Load Regulation I OUT = 1mA to 500mA Line Regulation 3.3 V 0.01 mV/mA VIN = 1.425V to 3.6V, VOUT = 1.2V, I OUT = 1mA 4 mV 40 150 mV 0.7 0.85 1.0 A 0.489 0.499 0.509 V 0.1 0.2 μA Dropout Voltage (VIN - VOUT) (Note 3) VDO I OUT = 500mA, V OUT = 1.2V, VIN = 1.5V Output Current Limit ILIM VFB = 300mV Threshold Accuracy VFB VOUT = 1.125V to 3.3V, VIN = (VOUT + 0.3V) to 3.6V, I OUT = 1mA to 500mA Input Current IFB VFB = 0.488V FB EN/SOFT-START Enable Input Threshold (MAX15030) VIH Enable Input Threshold (MAX15029) VIH Soft-Start Charging Current ISS 5 μA Soft-Start Reference Voltage VSS 0.499 V 165 °C 15 °C VIL VIL VBIAS = 5V VIN = 1.8V 1.05 0.4 1.05 0.4 V V THERMAL SHUTDOWN Thermal Shutdown Threshold Thermal Shutdown Hysteresis TJ rising Note 2: All devices are production tested at TA = +25°C. Limits over the operating temperature range are guaranteed by design and characterization. _______________________________________________________________________________________ 3 MAX15029/MAX15030 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (Circuit of Figure 1, VIN = 1.8V, VOUT = 1.5V, IOUT = 500mA, TA = +25°C, unless otherwise noted.) 1.0 0.8 0.6 1.49 1.48 1.47 0.4 1.46 IOUT = 0 VBIAS = 3.3V 0.2 1.0 1.5 2.0 2.5 3.0 3.5 0.4 VBIAS = 3.3V IOUT = 0 200 400 600 0 800 0.5 1.0 1.5 2.0 2.5 3.0 OUTPUT CURRENT (mA) INPUT VOLTAGE (V) BIAS CURRENT vs. BIAS VOLTAGE BIAS CURRENT vs. OUTPUT CURRENT GROUND CURRENT vs. OUTPUT CURRENT 60 MAX15029 toc04 60 40 30 20 58 57 56 55 54 53 VIN = 1.8V VOUT = 1.5V IOUT = 0 VBIAS = 3.3V 1.2 4 5 1.0 0.8 0.6 0.4 0.2 VBIAS = 3.3V 51 0 50 3 6 0 BIAS VOLTAGE (V) 200 400 600 100 0 800 200 300 400 OUTPUT CURRENT (mA) OUTPUT CURRENT (mA) DROPOUT VOLTAGE vs. OUTPUT CURRENT FEEDBACK VOLTAGE vs. TEMPERATURE 80 70 60 50 40 30 499.5 499.0 FEEDBACK VOLTAGE (mV) MAX15029 toc07 90 IOUT = 0 498.5 498.0 497.5 20 VOUT = 1.5V VBIAS = 3.3V 10 0 200 400 600 OUTPUT CURRENT (mA) 4 497.0 IOUT = 500mA 496.5 0 4.0 52 0 2 3.5 1.4 MAX15029 toc08 10 VBIAS = 5.5V 59 BIAS CURRENT (µA) 50 DROPOUT VOLTAGE (mV) 0.6 INPUT VOLTAGE (V) 70 1 0.8 0 0 4.0 GROUND CURRENT (mA) 0.5 MAX15029 toc05 0 1.0 0.2 1.45 0 MAX15029 toc03 1.2 MAX15029 toc06 1.50 OUTPUT VOLTAGE (V) 1.2 1.4 INPUT CURRENT (mA) 1.4 VBIAS = 3.3V MAX15029 toc02 1.51 MAX15029 toc01 1.6 OUTPUT VOLTAGE (V) INPUT CURRENT vs. INPUT VOLTAGE OUTPUT VOLTAGE vs. OUTPUT CURRENT OUTPUT VOLTAGE vs. INPUT VOLTAGE BIAS CURRENT (µA) MAX15029/MAX15030 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input 800 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (°C) _______________________________________________________________________________________ 500 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input OUTPUT VOLTAGE vs. OUTPUT CURRENT OUTPUT VOLTAGE vs. TEMPERATURE MAX15029 toc10 1.4 OUTPUT VOLTAGE (V) 1.52 OUTPUT VOLTAGE (V) 1.6 MAX15029 toc09 1.53 1.51 IOUT = 0 1.50 1.49 VIN = 1.8V 1.2 1.0 VIN = 1.2V 0.8 0.6 0.4 1.48 IOUT = 500mA 0 1.47 -50 -25 0 25 50 75 0 100 125 150 200 400 600 800 OUTPUT CURRENT (mA) TEMPERATURE (°C) CURRENT LIMIT vs. TEMPERATURE LOAD-TRANSIENT RESPONSE MAX15029 toc12 MAX15029 toc11 950 930 910 CURRENT LIMIT (mA) TA = +125°C VOUT = 1.5V 0.2 IOUT 890 20mA/div 870 0 850 830 10mV/div AC-COUPLED VOUT 810 790 770 IOUT = 100mA TO 500mA TO 100mA 750 -50 -25 0 25 50 75 100 125 150 20μs/div TEMPERATURE (°C) POWER-UP RESPONSE POWER-DOWN RESPONSE MAX15029 toc13 MAX15029 toc14 1V/div VOUT 1V/div 0 VOUT 0 1V/div 2V/div VIN VIN 0 IOUT = 500mA 0 IOUT = 500mA 2ms/div 20ms/div _______________________________________________________________________________________ 5 MAX15029/MAX15030 Typical Operating Characteristics (continued) (Circuit of Figure 1, VIN = 1.8V, VOUT = 1.5V, IOUT = 500mA, TA = +25°C, unless otherwise noted.) MAX15029/MAX15030 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input Typical Operating Characteristics (continued) (Circuit of Figure 1, VIN = 1.8V, VOUT = 1.5V, IOUT = 500mA, TA = +25°C, unless otherwise noted.) TURN-ON WITH ENABLE RESPONSE TURN-OFF WITH ENABLE RESPONSE MAX15029 toc15 MAX15029 toc16 1V/div 1V/div VOUT 0 VOUT 0 2V/div VEN 2V/div 0 0 VEN IOUT = 500mA IOUT = 500mA 2ms/div 4μs/div Pin Description PIN 6 NAME FUNCTION MAX15029 MAX15030 1, 2, 3 1, 2 IN Regulator Input. 1.425V to 3.6V voltage range. Bypass to GND with at least 1µF of ceramic capacitance. IN is high impedance when the LDO is shut down. — 3 BIAS Internal Circuitry Supply Input. BIAS supplies the power for the internal circuitry. 3V to 5.5V voltage range. 4 4 I.C. Internally Connected. Connect I.C. directly to GND. 5 5 EN LDO Enable. Drive EN high to enable the LDO or connect to IN (BIAS for MAX15030) for always-on operation. Drive EN low to disable the LDO and place the IC in low-power shutdown mode. 6 6 SS Soft-Start Input. For typical operation, connect a 0.1µF capacitor from SS to GND. The soft-start timing is dependent on the value of this capacitor. See the Soft-Start section. 7 7 FB Feedback Input. Connect FB to the center of a resistor-divider connected between OUT and GND to set the output voltage. See the Programming the Output Voltage section. 8 8 GND Ground 9, 10 9, 10 OUT Regulator Output. Bypass OUT to GND with at least 2.2µF of ceramic capacitance for 500mA load operation. — — EP Exposed Pad. Connect EP to GND and a large copper ground plane to facilitate package power dissipation. _______________________________________________________________________________________ 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input IN MAX15029 ONLY MAX15030 ONLY REF BIAS MAX15029 MAX15030 INTERNAL SUPPLY GENERATOR IN UVLO BIAS UVLO REF CONTROL LOGIC ERROR AMPLIFIER WITH SOFT-START EN MOS DRIVER WITH ILIMIT P OUT OVERTEMPERATURE PROTECTION SS FB GND Detailed Description The MAX15029/MAX15030 low-dropout linear regulators operate from input voltages as low as 1.425V and deliver up to 500mA of continuous output current with a maximum dropout voltage of only 150mV. The MAX15030 operates with an input voltage as low as 1.425V if the bias voltage (VBIAS) of 3V to 5.5V is available. The power is applied at IN while the control is provided through BIAS input. The current drawn by BIAS is negligible when the LDO goes into the shutdown. This feature is especially useful in automotive applications where the BIAS input is derived from an always-on LDO that expects to provide minimal power during the key-off condition. The pMOS output stage can be driven from input voltages down to +1.425V without sacrificing stability or transient performance. The output voltage of all the regulators is adjustable from 0.5V to VIN and is ±2% accurate over load and line variations, from -40°C to +125°C. Since these regulators have a pMOS output device, supply current is not a significant function of load or input headroom. _______________________________________________________________________________________ 7 MAX15029/MAX15030 Functional Diagram MAX15029/MAX15030 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input Internal p-Channel Pass Transistor Shutdown Mode The MAX15029/MAX15030 feature a 75mΩ (typ) p-channel MOSFET pass transistor. Unlike similar designs using pnp pass transistors, p-channel MOSFETs require no base drive, reducing quiescent current. pnp-based regulators also waste considerable current in dropout when the pass transistor saturates and uses high base-drive currents under large loads. The MAX15029/MAX15030 do not suffer from these problems and consume only 315µA (typ) of quiescent current under heavy loads, as well as in dropout. The MAX15029/MAX15030 include an enable input. To shut down the IC, drive EN low. In shutdown mode, the current drawn by BIAS is less than 2µA. This feature is extremely useful in an automotive application where the BIAS input is derived from an always-on LDO expecting to provide minimal dark current. For normal operation, drive EN high or connect EN to IN for continuous on operation. During shutdown, an internal 10kΩ resistor is connected between OUT and GND. Short-Circuit/ Thermal Fault Protection The MAX15029/MAX15030 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 a maximum of 1A. Under these conditions, the device quickly heats up. When the junction temperature reaches +165°C (typ), the thermal-overload circuitry turns off the output, allowing the part to cool down. When the junction temperature cools to +150°C (typ), the output turns back on and reestablishes 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. Applications Information Programming the Output Voltage The MAX15029/MAX15030 feature an adjustable output voltage from 0.5V to VIN 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 to be 10kΩ. Or, to optimize load-transient response for no load to full load transients, use the resistor-divider as a minimum load and choose R2 to be 500Ω. To simplify resistor selection: Soft-Start The MAX15029/MAX15030 feature a soft-start function that slowly ramps up the output voltage of the regulator based on the value of the capacitor (CSS) connected from SS to GND. Upon power-up, CSS is charged with a 5µA (typ) current source through SS. The voltage at SS is compared to the internal 0.5V reference (VREF). The feedback voltage for regulation (VREG) is the lower of VSS or VREF. As VSS rises, the regulation voltage (VREG) rises at the same rate. Once VSS reaches and rises above VREF, the regulation voltage then tracks the reference voltage since it is the lower of VSS and VREF. The value of CSS determines the length of the soft-start time, tSS. Use the following formula to determine CSS. CSS = 10-5 x tSS where CSS is in farads and tSS is in seconds. ALWAYS-ON INPUT 3V TO 5.5V INPUT 1.425V TO 3.6V ⎛V R1 = R2 ⎜ OUT ⎝ VFB − 1⎟ ⎞ BIAS OUT ⎠ OUTPUT IN R1 1μF MAX15030 ENABLE FB I.C. EN SHUTDOWN GND SS 0.1uF Figure 1. MAX15030 Typical Application Circuit 8 _______________________________________________________________________________________ 2.2μF R2 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input Capacitors are required at the MAX15029/MAX15030’s inputs and outputs for stable operation over the full temperature range and with load currents up to 500mA. Connect a 1µF capacitor between IN and ground and a 2.2µF capacitor with low equivalent series resistance (ESR) between OUT and ground for 500mA 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 500mA. Calculate the minimum COUT as follows: ⎛ 1μ F ⎞ C OUT = IOUT(MAX) × ⎜ ⎝ 0. 25A ⎟⎠ Noise, PSRR, and Transient Response The MAX15029/MAX15030 are designed to operate with low-dropout voltages and low quiescent currents while still maintaining good noise performance, transient response, and AC rejection (see the Typical Operating Characteristics). 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 MAX15029/MAX15030 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 100mA to 500mA is 10mV. Use ceramic output capacitors greater than 2.2µF (up to 100µF) to attenuate the overshoot. Layout Guidelines Operating Region and Power Dissipation 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 DISS = I OUT (V IN - V OUT). 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 PCB. 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 and multiple vias to the ground plane layer. The TDFN package has an exposed thermal pad on its underside. This pad provides a low thermal resistance path for heat transfer into the PCB. This low thermally resistive path carries a majority of the heat away from the IC. The PCB is effectively a heatsink for the IC. The exposed pad should be connected to a large ground plane for proper thermal and electrical performance. The minimum size of the ground plane is dependent upon many system variables. To create an efficient path, the exposed pad should be soldered to a thermal landing, which is connected to the ground plane by thermal vias. The thermal landing should be at least as large as the exposed pad. _______________________________________________________________________________________ 9 MAX15029/MAX15030 Capacitor Selection and Regulator Stability MAX15029/MAX15030 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input Typical Operating Circuits OUTPUT 0.5V TO VIN OUT INPUT 1.425V TO 3.6V ALWAYS-ON INPUT 3V TO 5.5V BIAS INPUT 1.425V TO 3.6V IN OUT OUTPUT 0.5V TO VIN IN 1μF 1μF MAX15029 FB MAX15030 2.2μF EN FB 2.2μF EN GND SS SS Pin Configurations (continued) GND Chip Information PROCESS: BiCMOS TOP VIEW Package Information IN 1 IN 2 BIAS 3 I.C. 4 EN 5 + MAX15030 EP For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. 10 OUT 9 OUT 8 GND 7 FB PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 6 SS 10 TDFN-EP T1033+1 21-0137 90-0003 TDFN (3mm x 3mm) 10 ______________________________________________________________________________________ 1.425V to 3.6V Input, 500mA Low-Dropout Regulators with BIAS Input REVISION NUMBER REVISION DATE 0 4/09 Initial release 2/11 Added the MAX15029 automotive qualified part to the Ordering Information table; added soldering information to the Absolute Maximum Ratings section; added the Package Thermal Characteristics section; added the land pattern no. to the Package Information table 1 DESCRIPTION PAGES CHANGED — 1, 2, 10 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 ____________________ 11 © 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX15029/MAX15030 Revision History