S P X1 5 8 7 3A Low Dropout Voltage Regulator September 2010 Rev. 2.0.0 GENERAL DESCRIPTION APPLICATIONS The SPX1587 is a low power positive-voltage regulator designed to satisfy moderate power requirements with a cost effective, small footprint solution. * Desktop PC's Servers This device is an excellent choice for use in battery-powered applications and portable computers. The SPX1587 features very low quiescent current and a low dropout voltage of 1.1V at a full load. As output current decreases, quiescent current flows into the load, increasing efficiency. SPX1587 is available in adjustable or fixed 1.5V, 2.5V, 3.3V and 5.0V output voltages. * Portable Instrumentation The SPX1587 is offered in several 3-pin surface mount packages: TO-252, TO-220 and TO-263. An output capacitor of 10F ceramic or tantalum provides unconditional stability. * Powering VGA and Sound Cards * Adjustable Power Supplies FEATURES * Guaranteed 3A Output Current * Three Terminal Adjustable or Fixed 1.5V, 2.5V, 3.3V and 5.0V * Low Quiescent Current * Low Dropout Voltage: 1.1V at 3A * Line Regulation: 0.1% * Load Regulation: 0.1% * Stable with 10uF Ceramic Capacitor * Over Current and Thermal Protection * Similar to Industry Standard LT1085/LT1585 * RoHS Compliant Lead Free 3-Pin TO-220, TO-252 and TO-263 Packages FUNCTIONAL DIAGRAM Fig. 1: SPX1587 Functional Diagram (Adjustable version) Exar Corporation 48720 Kato Road, Fremont CA 94538, USA www.exar.com Tel. +1 510 668-7000 - Fax. +1 510 668-7001 S P X1 5 8 7 3A Low Dropout Voltage Regulator ABSOLUTE MAXIMUM RATINGS OPERATING RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. Junction Temperature Range ....................-40C to 125C Thermal Resistance TO-220 JC ...................................................... 3C/W TO-220 JA ................................................. 29.4C/W TO-263 JC ...................................................... 3C/W TO-263 JA ................................................. 31.4C/W TO-252 JC ...................................................... 6C/W TO-252 JA .................................................... 50C/W Input Supply Voltage VIN .................................... +10.0V Input to Output Voltage ....................................... +8.8V Storage Temperature .............................. -65C to 150C Power Dissipation ................................ Internally Limited Lead Temperature (Soldering, 5 sec) ..................... 260C ESD Rating (HBM - Human Body Model) .................... 2kV ELECTRICAL SPECIFICATIONS Specifications with standard type are for an Operating Ambient Temperature of TA = 25C only; limits applying over the full Operating Temperature range (-40C to +85C) are denoted by a "*". Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm at TA = 25C, and are provided for reference purposes only. Unless otherwise indicated, VIN = VOUT + 1.5V, TA = 25C, CIN = COUT =10F, IOUT=10mA. Parameter Min. Typ. 1.485 1.500 Max. Units Conditions 1.5V Version Output Voltage SPX1587A 1.515 1.530 1.470 V IOUT=10mA, VOUT=3.5V * 10mAIOUT3A, 3.0VVOUT10V * 10mAIOUT3A, 4.25VIOUT10V * 10mAIOUT3A, 4.75VVOUT10V * 10mAIOUT3A, 4.75VVOUT10V * 10mAIOUT3A, 6.50VVOUT10V * 10mAIOUT3A, 1.50VVIN-VOUT10V * 10mAIOUT3A, 1.50VVIN-VOUT10V 2.5V Version Output Voltage SPX1587 2.450 2.500 2.550 2.575 2.425 V IOUT=10mA, VOUT=4.5V 3.3V Version 3.267 Output Voltage SPX1587A 3.234 Output Voltage SPX1587 3.201 3.234 3.300 3.333 3.366 3.300 3.366 3.399 V V IOUT=10mA, VOUT=5V IOUT=10mA, VOUT=5V 5.0V Version Output Voltage SPX1587A 4.950 5.000 5.050 5.100 4.900 V IOUT=10mA, VOUT=7V All Voltage Options 1.238 Reference Voltage SPX1587A 1.225 Reference Voltage SPX1587 1.212 1.225 1.250 1.262 1.275 1.250 1.275 1.287 V V Output Voltage Temperature Stability - SPX1587A 0.3 % Output Voltage Temperature Stability - SPX1587 0.5 % IOUT=10mA, VIN-VOUT=2V IOUT=10mA, VIN-VOUT=2V 3.0VVIN10V, VOUT=1.5V Line Regulation 0.1 0.2 % 4.25VVIN10V, VOUT=2.5V 4.75VVIN10V, VOUT=3.3V 6.50VVIN10V, VOUT=5.0V 10mAIOUT3A, VOUT=1.5V Load Regulation 0.1 0.3 % 10mAIOUT3A, VOUT=2.5V 10mAIOUT3A, VOUT=3.3V 10mAIOUT3A, VOUT=5.0V (c) 2010 Exar Corporation 2/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator Parameter Min. Typ. Max. Units Conditions IOUT=1A 1.00 Dropout Voltage (note 2) Minimum Load Current (note 4) Quiescent Current Current Limit 1.2 4 10 mA 4 10 mA 5 0.01 Fixed Voltage Versions A 120 3.2 Thermal Regulation Ripple Rejection IOUT=3A 1.10 50 Adjust Pin Current IOUT=2A V 1.05 A * A 0.1 %/W VIN-VOUT=2V 25C, 30ms pulse 75 dB FRIPPLE=120Hz, VIN-VOUT=2V, VRIPPLE=1VPP Long Term Stability 0.03 % 125C, 1000 hours RMS Output Noise 0.03 % % of VOUT, 10Hz f 10kHz 60 Note 1: Output temperature coefficient is defined as the worst case voltage change divided by the total temperature range Note 2: Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV below its nominal value measured at 1V differential at very low values of programmed output voltage, the minimum input supply voltage of 2V (2.3V over temperature) must be taken into account. Note 3: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied. Excluding load or line regulation effect. Note 4: Adjustable Version Only. BLOCK DIAGRAM Fig. 2: SPX1587 Block Diagram (c) 2010 Exar Corporation 3/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator PIN ASSIGNMENT Fig. 3: SPX1587 Pin Assignment PIN DESCRIPTION Name Pin Number ADJ/GND 1 Description Adjustable Voltage Pin or Ground signal for fixed voltage versions. VOUT 2 Output Voltage VIN 3 Input Voltage TAB TAB Tab is connected to VOUT (pin 2) for all packages ORDERING INFORMATION Part Number SPX1587T-L SPX1587T-L/TR SPX1587T-L-1-5 SPX1587T-L-1-5/TR SPX1587T-L-5-0 SPX1587T-L-5-0/TR Junction Temperature Range -40CTJ+125C -40CTJ+125C -40CTJ+125C SPX1587U-L-3-3 -40CTJ+125C SPX1587U-L-5-0 -40CTJ+125C SPX1587AR-L SPX1587AR-L/TR SPX1587AT-L SPX1587AT-L/TR SPX1587AT-L-2-5 SPX1587AT-L-2-5/TR SPX1587AT-L-3-3 SPX1587AT-L-3-3/TR SPX1587AU-L -40CTJ+125C -40CTJ+125C -40CTJ+125C -40CTJ+125C -40CTJ+125C Marking Sipex SPX1587T YYWWLX Sipex SPX1587T 15YYWWLX Sipex SPX1587T 50YYWWLX Sipex SPX1587U 33YYWWLX Sipex SPX1587U 50YYWWLX Sipex SPX1587AR YYWWLX Sipex SPX1587AT YYWWLX Sipex SPX1587AT 25YYWWLX Sipex SPX1587AT 33YYWWLX Sipex SPX1587AU YYWWLX Package TO263-3 TO263-3 TO263-3 Packing Quantity Bulk 500/Tape & Reel Bulk 500/Tape & Reel Bulk 500/Tape & Reel Note 1 Lead Free Lead Free Lead Free TO220-3 Bulk Lead Free TO220-3 Bulk Lead Free TO252-3 TO263-3 TO263-3 TO263-3 TO220-3 Bulk 2K/Tape & Reel Bulk 500/Tape & Reel Bulk 500/Tape & Reel Bulk 500/Tape & Reel Bulk Lead Free Lead Free Lead Free Lead Free Lead Free "YY" = Year - "WW" = Work Week - "L" = Lead Free Indicator - "X" = Lot Number; when applicable. (c) 2010 Exar Corporation 4/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator TYPICAL PERFORMANCE CHARACTERISTICS All data taken at VIN = VOUT + 1.5V, TA = 25C, CIN = COUT =10F, IOUT=10mA unless otherwise specified - Schematic and BOM from Application Information section of this datasheet. Fig. 4: Line Regulation for SPX1587U-3-3 IOUT=10mA Fig. 5: VOUT versus Temperature VIN=2.5V, IOUT=10mA Fig. 6: VOUT versus Temperature VIN=4.0V, IOUT=10mA Fig. 7: VOUT versus Temperature VIN=5.0V, IOUT=10mA SOLDERING METHODS APPLICATION INFORMATION The SPX1587 die is attached to the heatsink lead which exits opposite the input, output, and ground pins. OUTPUT CAPACITOR To ensure the stability of the SPX1587, an output capacitor of at least 10F (ceramic or tantalum) or 22F (aluminum) is required. The value may change based on the application requirements of the output load or temperature range. The value of ESR can vary based on the type of capacitor used in the applications to guarantee stability. The recommended value for ESR is 0.5 or less. A larger value of output capacitance (up to 100F) can improve the load transient response. (c) 2010 Exar Corporation THERMAL CHARACTERISTICS The SPX1587 features the internal thermal limiting to protect the device during overload conditions. Special care needs to be taken during continuous load conditions such that the maximum junction temperature does not exceed 125C. Thermal protection is activated at >179C and deactivated at <165 C. The thermal interaction from other components in the application can affect the 5/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator If an ADJ-bypass capacitor is used, the amplitude of the output ripple will be independent of the output voltage. If an ADJbypass capacitor is not used, the output ripple will be proportional to the ratio of the output voltage to the reference voltage: thermal resistance of the SPX1587. The actual thermal resistance can be determined with experimentation. The SPX1587 power dissipation is calculated as follows: Maximum Junction Temperature range: Where M = multiplier for the ripple seen when the ADJ pin is optimally bypassed. VREF=1.25V Where JA is the junction-to-ambient thermal resistance of the package. Maximum junction exceed 125C. temperature must Ripple rejection for the adjustable version is showing in Figure 8. not OUTPUT VOLTAGE RIPPLE REJECTION The output of the adjustable regulator can be set to any voltage between 1.25V and 15V. The value of VOUT can be quickly approximated using the formula Ripple rejection can be improved by adding a capacitor between the ADJ pin and ground as shown in Figure 11. When ADJ pin bypassing is used, the value of the output capacitor required increases to its maximum. If the ADJ pin is not bypassed, the value of the output capacitor can be lowered to 22F for an electrolytic aluminum capacitor or 10F for a solid tantalum capacitor (Fig 10). 1.25 Small correction to this formula is required depending on the values of resistors R1 and R2, since the adjustable pin current (approx 50A) flows through R2. When IADJ is taken into account, the formula becomes However the value of the ADJ-bypass capacitor should be chosen with respect to the following equation: 1 1 Where 6.28 VREF=1.25V Where LAYOUT CONSIDERATIONS C = value of the capacitor in Farads (select an equal or larger standard value) Parasitic line resistance can degrade load regulation. In order to avoid this, connect R1 directly to VOUT as illustrated in Figure 13. For the same reason, R2 should be connected to the negative side of the load. FR= ripple frequency in Hz R1= value of resistor R1 in Ohms. (c) 2010 Exar Corporation 6/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator Fig. 8: Ripple Rejection VIN=3.3V, VOUT=1.8V(adj), ILOAD=200mA Fig. 9: Current Source Fig. 10: Typical Adjustable Regulator Fig. 11: Improving Ripple Rejection Fig. 12: 5V Regulator With Shutdown Fig. 13: Recommended Connections for Best Results (c) 2010 Exar Corporation 7/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator PACKAGE SPECIFICATION 3-PIN TO263 (c) 2010 Exar Corporation 8/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator 3-PIN TO220 (c) 2010 Exar Corporation 9/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator 3-PIN TO252 (c) 2010 Exar Corporation 10/11 Rev. 2.0.0 S P X1 5 8 7 3A Low Dropout Voltage Regulator REVISION HISTORY Revision Date 2.0.0 Description Reformat of datasheet Added marking information FOR FURTHER ASSISTANCE Email: customersupport@exar.com Exar Technical Documentation: http://www.exar.com/TechDoc/default.aspx? EXAR CORPORATION HEADQUARTERS AND SALES OFFICES 48720 Kato Road Fremont, CA 94538 - USA Tel.: +1 (510) 668-7000 Fax: +1 (510) 668-7030 www.exar.com NOTICE EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration purposes and may vary depending upon a user's specific application. While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances. or its in all Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. (c) 2010 Exar Corporation 11/11 Rev. 2.0.0