LP2981 Micropower 100 mA Ultra Low-Dropout Regulator General Description Features The LP2981 is a 100 mA, fixed-output voltage regulator designed specifically to meet the requirements of battery-powered applications. Using an optimized VIP™ (Vertically Integrated PNP) process, the LP2981 delivers unequaled performance in all specifications critical to battery-powered designs: Dropout Voltage. Typically 200 mV @ 100 mA load, and 7 mV @ 1 mA load. Ground Pin Current. Typically 600 µA @ 100 mA load, and 80 µA @ 1 mA load. Sleep Mode. Less than 1 µA quiescent current when ON/ OFF pin is pulled low. Smallest Possible Size. SOT-23and micro SMD packages use an absolute minimum board space. Precision Output. 0.75% tolerance output voltages available (A grade). Eleven voltage options, from 2.5V to 5.0V, are available as standard products. n n n n n n n n n n n n Ultra low dropout voltage Output voltage accuracy 0.75% (A Grade) Guaranteed 100 mA output current Smallest possible size (SOT-23, micro SMD package) < 1 µA quiescent current when shutdown Low ground pin current at all load currents High peak current capability (300 mA typical) Wide supply voltage range (16V max) Fast dynamic response to line and load Low ZOUT over wide frequency range Overtemperature/overcurrent protection −40˚C to +125˚C junction temperature range Applications n n n n Cellular Phone Palmtop/Laptop Computer Personal Digital Assistant (PDA) Camcorder, Personal Stereo, Camera Block Diagram DS012506-1 VIP™ is a trademark of National Semiconductor Corporation. © 2000 National Semiconductor Corporation DS012506 www.national.com LP2981 Micropower 100 mA Ultra Low-Dropout Regulator March 2000 LP2981 Connection Diagrams 5-Lead Small Outline Package (M5) micro SMD, 5 Bump Package (BPA05) DS012506-50 DS012506-2 Bottom View See NS Package Number BPA05 Top View See NS Package Number MF05A For ordering information see Table 1 Ordering Information TABLE 1. Package Marking and Order Information Output Voltage (V) Grade Order Information Package Marking Supplied as: 5-Lead Small Outline Package (M5) 2.5 A LP2981AIM5X-2.5 L0CA 3000 Units on Tape and Reel 2.5 A LP2981AIM5-2.5 L0CA 1000 Units on Tape and Reel 2.5 STD LP2981IM5X-2.5 L0CB 3000 Units on Tape and Reel 2.5 STD LP2981IM5-2.5 L0CB 1000 Units on Tape and Reel 2.7 A LP2981AIM5X-2.7 L0DA 3000 Units on Tape and Reel 2.7 A LP2981AIM5-2.7 L0DA 1000 Units on Tape and Reel 2.7 STD LP2981IM5X-2.7 L0DB 3000 Units on Tape and Reel 2.7 STD LP2981IM5-2.7 L0DB 1000 Units on Tape and Reel 2.8 A LP2981AIM5X-2.8 L77A 3000 Units on Tape and Reel 2.8 A LP2981AIM5-2.8 L77A 1000 Units on Tape and Reel 2.8 STD LP2981IM5X-2.8 L77B 3000 Units on Tape and Reel 2.8 STD LP2981IM5-2.8 L77B 1000 Units on Tape and Reel 2.9 A LP2981AIM5X-2.9 L0VA 3000 Units on Tape and Reel 2.9 A LP2981AIM5-2.9 L0VA 1000 Units on Tape and Reel 2.9 STD LP2981IM5X-2.9 L0VB 3000 Units on Tape and Reel 2.9 STD LP2981IM5-2.9 L0VB 1000 Units on Tape and Reel 3.0 A LP2981AIM5X-3.0 L05A 3000 Units on Tape and Reel 3.0 A LP2981AIM5-3.0 L05A 1000 Units on Tape and Reel 3.0 STD LP2981IM5X-3.0 L05B 3000 Units on Tape and Reel 3.0 STD LP2981IM5-3.0 L05B 1000 Units on Tape and Reel 3.1 A LP2981AIM5X-3.1 L38A 3000 Units on Tape and Reel 3.1 A LP2981AIM5-3.1 L38A 1000 Units on Tape and Reel 3.1 STD LP2981IM5X-3.1 L38B 3000 Units on Tape and Reel 3.1 STD LP2981IM5-3.1 L38B 1000 Units on Tape and Reel 3.2 A LP2981AIM5X-3.2 L35A 3000 Units on Tape and Reel 3.2 A LP2981AIM5-3.2 L35A 1000 Units on Tape and Reel 3.2 STD LP2981IM5X-3.2 L35B 3000 Units on Tape and Reel 3.2 STD LP2981IM5-3.2 L35B 1000 Units on Tape and Reel 3.3 A LP2981AIM5X-3.3 L04A 3000 Units on Tape and Reel 3.3 A LP2981AIM5-3.3 L04A 1000 Units on Tape and Reel 3.3 STD LP2981IM5X-3.3 L04B 3000 Units on Tape and Reel 3.3 STD LP2981IM5-3.3 L04B 1000 Units on Tape and Reel www.national.com 2 LP2981 Ordering Information (Continued) TABLE 1. Package Marking and Order Information (Continued) Output Voltage (V) Grade Order Information Package Marking Supplied as: 5-Lead Small Outline Package (M5) 3.6 A LP2981AIM5X-3.6 L0JA 3000 Units on Tape and Reel 3.6 A LP2981AIM5-3.6 L0JA 1000 Units on Tape and Reel 3.6 STD LP2981IM5X-3.6 L0JB 3000 Units on Tape and Reel 3.6 STD LP2981IM5-3.6 L0JB 1000 Units on Tape and Reel 3.8 A LP2981AIM5X-3.8 L36A 3000 Units on Tape and Reel 3.8 A LP2981AIM5-3.8 L36A 1000 Units on Tape and Reel 3.8 STD LP2981IM5X-3.8 L36B 3000 Units on Tape and Reel 3.8 STD LP2981IM5-3.8 L36B 1000 Units on Tape and Reel 4.0 A LP2981AIM5X-4.0 L0ZA 3000 Units on Tape and Reel 4.0 A LP2981AIM5-4.0 L0ZA 1000 Units on Tape and Reel 4.0 STD LP2981IM5X-4.0 L0ZB 3000 Units on Tape and Reel 4.0 STD LP2981IM5-4.0 L0ZB 1000 Units on Tape and Reel 4.7 A LP2981AIM5X-4.7 L0GA 3000 Units on Tape and Reel 4.7 A LP2981AIM5-4.7 L0GA 1000 Units on Tape and Reel 4.7 STD LP2981IM5X-4.7 L0GB 3000 Units on Tape and Reel 4.7 STD LP2981IM5-4.7 L0GB 1000 Units on Tape and Reel 5.0 A LP2981AIM5X-5.0 L03A 3000 Units on Tape and Reel 5.0 A LP2981AIM5-5.0 L03A 1000 Units on Tape and Reel 5.0 STD LP2981IM5X-5.0 L03B 3000 Units on Tape and Reel 5.0 STD LP2981IM5-5.0 L03B 1000 Units on Tape and Reel micro SMD, 5 Bump Package (BPA05) 2.5 A LP2981AIBP-2.5 250 Units on Tape and Reel 2.5 A LP2981AIBPX-2.5 3000 Units on Tape and Reel 2.5 STD LP2981IBP-2.5 250 Units on Tape and Reel 2.5 STD LP2981IBPX-2.5 3000 Units on Tape and Reel 3.2 A LP2981AIBP-3.2 250 Units on Tape and Reel 3.2 A LP2981AIBPX-3.2 3000 Units on Tape and Reel 3.2 STD LP2981IBP-3.2 250 Units on Tape and Reel 3.2 STD LP2981IBPX-3.2 3000 Units on Tape and Reel 3.3 A LP2981AIBP-3.3 250 Units on Tape and Reel 3.3 A LP2981AIBPX-3.3 3000 Units on Tape and Reel 3.3 STD LP2981IBP-3.3 250 Units on Tape and Reel 3.3 STD LP2981IBPX-3.3 3000 Units on Tape and Reel 3 www.national.com LP2981 Absolute Maximum Ratings (Note 1) Power Dissipation (Note 3) Input Supply Voltage (Survival) Input Supply Voltage (Operating) Shutdown Input Voltage (Survival) Output Voltage (Survival, (Note 4)) IOUT (Survival) Input-Output Voltage (Survival, (Note 5)) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Storage Temperature Range Operating Junction Temperature Range Lead Temperature (Soldering, 5 sec.) ESD Rating (Note 2) −65˚C to +150˚C −40˚C to +125˚C Internally Limited −0.3V to +16V 2.1V to +16V −0.3V to +16V −0.3V to +9V Short Circuit Protected −0.3V to +16V 260˚C 2 kV Electrical Characteristics Limits in standard typeface are for TJ = 25˚C, and limits in boldface type applyover the full operating temperature range. Unless otherwise specified: VIN = VO(NOM) + 1V, CIN = 1 µF, IL = 1 mA, COUT = 4.7 µF,VON/OFF = 2V. Symbol Parameter Conditions Typ LP2981AI-XX (Note 6) ∆VO VIN–VO Output Voltage Tolerance Max Min Max IL = 1mA −0.75 0.75 −1.25 1.25 1 mA < IL < 100 mA −1.0 1.0 −2.0 2.0 −2.5 2.5 −3.5 3.5 Output Voltage VO(NOM) + 1V Line Regulation ≤ VIN ≤ 16V Dropout Voltage IL = 0 0.007 1 IL = 1 mA Ground Pin Current 7 IL = 25 mA 70 IL = 100 mA 200 IL = 0 65 IL = 1 mA 80 IL = 25 mA 200 IL = 100 mA VON/OFF ION/OFF 600 0.014 0.014 0.032 0.032 3 3 5 5 10 10 15 15 100 100 150 150 250 250 375 375 95 95 125 125 110 110 170 170 300 300 550 550 800 800 1500 1500 0.8 VON/OFF < 0.3V 0.01 0.8 VON/OFF < 0.15V 0.05 2 ON/OFF Input Voltage High = O/P ON 1.4 (Note 8) Low = O/P OFF 0.50 0.15 0.15 ON/OFF Input Current VON/OFF = 0 0.01 −1 −1 5 15 15 VON/OFF = 5V Units (Note 6) Min (Note 7) IGND LP2981I-XX 1.6 %VNOM %/V mV µA 2 1.6 V µA VOUT ≥ VO(NOM) − 5% 400 Output Noise BW = 300 Hz–50 kHz, 160 µV Voltage (RMS) COUT = 10 µF Ripple Rejection f = 1 kHz 63 dB 150 mA IO(PK) Peak Output Current en 150 150 mA COUT = 10 µF IO(MAX) Short Circuit Current RL = 0 (Steady State) (Note 9) www.national.com 4 (Continued) Note 1: Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the device outside of its rated operating conditions. Note 2: The ESD rating of pins 3 and 4 is 1 kV. Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal resistance, θJA, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated using: The value of θJA for the SOT-23 package is 220˚C/W and the micro SMD package is 320˚C/W. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. Note 4: If used in a dual-supply system where the regulator load is returned to a negative supply, the LP2981 output must be diode-clamped to ground. Note 5: The output PNP structure contains a diode between the VIN and VOUT terminals that is normally reverse-biased. Reversing the polarity from VIN to VOUT will turn on this diode (see Application Hints). Note 6: Limits are 100% production tested at 25˚C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control (SQC) methods. The limits are used to calculate National’s Average Outgoing Quality Level (AOQL). Note 7: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a 1V differential. Note 8: The ON/OFF inputs must be properly driven to prevent misoperation. For details, refer to Application Hints. Note 9: See Typical Performance Characteristics curves. Basic Application Circuit DS012506-4 *ON/OFF input must be actively terminated. Tie to VIN if this function is not to be used. **Minimum Output Capacitance is shown to insure stability over full load current range. More capacitance provides superior dynamic performance and additional stability margin (see Application Hints). ***Do not make connections to this pin. 5 www.national.com LP2981 Electrical Characteristics LP2981 Typical Performance Characteristics Unless otherwise specified: TA = 25˚C, VIN = VO(NOM) + 1V, COUT = 4.7 µF, CIN = 1 µF all voltage options, ON/OFF pin tied to VIN. Output Voltage vs Temperature Output Voltage vs Temperature DS012506-7 DS012506-6 Output Voltage vs Temperature Dropout Characteristics DS012506-9 DS012506-8 Dropout Characteristics Dropout Characteristics DS012506-11 DS012506-10 www.national.com 6 Unless otherwise specified: TA = 25˚C, VIN = VO(NOM) + 1V, COUT = 4.7 µF, CIN = 1 µF all voltage options, ON/OFF pin tied to VIN. (Continued) Dropout Voltage vs Temperature Dropout Voltage vs Load Current DS012506-12 Ground Pin Current vs Temperature DS012506-13 Ground Pin Current vs Load Current DS012506-14 Input Current vs VIN DS012506-15 Input Current vs VIN DS012506-17 DS012506-16 7 www.national.com LP2981 Typical Performance Characteristics LP2981 Typical Performance Characteristics Unless otherwise specified: TA = 25˚C, VIN = VO(NOM) + 1V, COUT = 4.7 µF, CIN = 1 µF all voltage options, ON/OFF pin tied to VIN. (Continued) Line Transient Response Line Transient Response DS012506-18 Load Transient Response DS012506-19 Load Transient Response DS012506-21 DS012506-20 Load Transient Response Load Transient Response DS012506-22 www.national.com DS012506-23 8 Unless otherwise specified: TA = 25˚C, VIN = VO(NOM) + 1V, COUT = 4.7 µF, CIN = 1 µF all voltage options, ON/OFF pin tied to VIN. (Continued) Short Circuit Current Instantaneous Short Circuit Current vs Temperature DS012506-24 DS012506-25 Short Circuit Current Instantaneous Short Circuit Current vs Output Voltage DS012506-26 DS012506-27 Output Impedance vs Frequency Ripple Rejection DS012506-29 DS012506-28 9 www.national.com LP2981 Typical Performance Characteristics LP2981 Typical Performance Characteristics Unless otherwise specified: TA = 25˚C, VIN = VO(NOM) + 1V, COUT = 4.7 µF, CIN = 1 µF all voltage options, ON/OFF pin tied to VIN. (Continued) Output Noise Density Output Impedance vs Frequency DS012506-30 DS012506-31 Input to Output Leakage vs Temperature Output Reverse Leakage vs Temperature DS012506-32 Turn-On Waveform DS012506-33 Turn-Off Waveform DS012506-35 DS012506-34 www.national.com 10 Unless otherwise specified: TA = 25˚C, VIN = VO(NOM) + 1V, COUT = 4.7 µF, CIN = 1 µF all voltage options, ON/OFF pin tied to VIN. (Continued) ON/OFF Pin Current vs VON/OFF ON/OFF Threshold vs Temperature DS012506-37 DS012506-36 CERAMIC: Ceramic capacitors are not recommended for use at the output of the LP2981. This is because the ESR of a ceramic can be low enough to go below the minimum stable value for the LP2981. A 2.2 µF ceramic was measured and found to have an ESR of about 15 mΩ, which is low enough to cause oscillations. If a ceramic capacitor is used on the output, a 1Ω resistor should be placed in series with the capacitor. ALUMINUM: Because of large physical size, aluminum electrolytics are not typically used with the LP2981. They must meet the same ESR requirements over the operating temperature range, more difficult because of their steep increase at cold temperature. An aluminum electrolytic can exhibit an ESR increase of as much as 50X when going from 20˚C to −40˚C. Also, some aluminum electrolytics are not operational below −25˚C because the electrolyte can freeze. Application Hints EXTERNAL CAPACITORS Like any low-dropout regulator, the external capacitors used with the LP2981 must be carefully selected to assure regulator loop stability. INPUT CAPACITOR: An input capacitor whose value is ≥ 1 µF is required with the LP2981 (amount of capacitance can be increased without limit). This capacitor must be located a distance of not more than 0.5" from the input pin of the LP2981 and returned to a clean analog ground. Any good quality ceramic or tantalum can be used for this capacitor. OUTPUT CAPACITOR: The output capacitor must meet both the requirement for minimum amount of capacitance and E.S.R. (equivalent series resistance) value. Curves are provided which show the allowable ESR range as a function of load current for various output voltages and capacitor values (refer to Figures 1, 2, 3, 4). IMPORTANT: The output capacitor must maintain its ESR in the stable region over the full operating temperature range to assure stability. Also, capacitor tolerance and variation with temperature must be considered to assure the minimum amount of capacitance is provided at all times. This capacitor should be located not more than 0.5" from the output pin of the LP2981 and returned to a clean analog ground. CAPACITOR CHARACTERISTICS TANTALUM: Tantalum capacitors are the best choice for use with the LP2981. Most good quality tantalums can be used with the LP2981, but check the manufacturer’s data sheet to be sure the ESR is in range. It is important to remember that ESR increases at lower temperatures and a capacitor that is near the upper limit for stability at room temperature can cause instability when it gets cold. In applications which must operate at very low temperatures, it may be necessary to parallel the output tantalum capacitor with a ceramic capacitor to prevent the ESR from going up too high (see next section for important information on ceramic capacitors). DS012506-38 FIGURE 1. 5V/3.3 µF ESR Curves 11 www.national.com LP2981 Typical Performance Characteristics LP2981 Application Hints (Continued) DS012506-41 If the output is forced above the input by more than a VBE, this diode will become forward biased and current will flow from the VOUT terminal to VIN. This current must be limited to < 100 mA to prevent damage to the part. The internal diode can also be turned on by abruptly stepping the input voltage to a value below the output voltage. To prevent regulator mis-operation, a Schottky diode should be used in any application where input/output voltage conditions can cause the internal diode to be turned on (see below). DS012506-39 FIGURE 2. 5V/10 µF ESR Curves DS012506-43 As shown, the Schottky diode is connected in parallel with the internal parasitic diode and prevents it from being turned on by limiting the voltage drop across it to about 0.3V. ON/OFF INPUT OPERATION The LP2981 is shut off by pulling the ON/OFF input low, and turned on by driving the input high. If this feature is not to be used, the ON/OFF input should be tied to VIN to keep the regulator on at all times (the ON/OFF input must not be left floating). To ensure proper operation, the signal source used to drive the ON/OFF input must be able to swing above and below the specified turn-on/turn-off voltage thresholds which guarantee an ON or OFF state (see Electrical Characteristics). The ON/OFF signal may come from either a totem-pole output, or an open-collector output with pull-up resistor to the LP2981 input voltage or another logic supply. The high-level voltage may exceed the LP2981 input voltage, but must remain within the Absolute Maximum Ratings for the ON/OFF pin. It is also important that the turn-on/turn-off voltage signals applied to the ON/OFF input have a slew rate which is greater than 40 mV/µs. Important: the regulator shutdown function will operate incorrectly if a slow-moving signal is applied to the ON/OFF input. DS012506-40 FIGURE 3. 3V/3.3 µF ESR Curves DS012506-42 FIGURE 4. 3V/10 µF ESR Curves Micro SMD Mounting The micro SMD package requires specific mounting techniques which are detailed in National Semiconductor Application Note # 1112. Referring to the section Surface Mount Technology (SMT) Assembly Considerations, it should be noted that the pad style which must be used with the 5-pin package is the NSMD (non-solder mask defined) type. REVERSE CURRENT PATH The power transistor used in the LP2981 has an inherent diode connected between the regulator input and output (see below). www.national.com 12 The wavelenghts which have the most detrimental effect are reds and infra-reds, which means that the fluorescent lighting used inside most buildings has very little effect on performance. A micro SMD test board was brought to within 1 cm of a fluorescent desk lamp and the effect on the regulated output voltage was negligible, showing a deviation of less than 0.1% from nominal. (Continued) For best results during assembly, alignment ordinals on the PC board may be used to facilitate placement of the micro SMD device. Micro SMD Light Sensitivity Exposing the micro SMD device to direct sunlight will cause misoperation of the device. Light sources such as Halogen lamps can also affect electrical performance if brought near to the device. 13 www.national.com LP2981 Application Hints LP2981 Physical Dimensions inches (millimeters) unless otherwise noted 5-Lead Small Outline Package (M5) NS Package Number MF05A For Order Numbers, refer to Table 1 in the “Ordering Information” section of this document. www.national.com 14 LP2981 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) NOTES: UNLESS OTHERWISE SPECIFIED 1. EPOXY COATING 2. 63Sn/37Pb EUTECTIC BUMP 3. RECOMMEND NON-SOLDER MASK DEFINED LANDING PAD. 4. PIN 1 IS ESTABLISHED BY LOWER LEFT CORNER WITH RESPECT TO TEXT ORIENTATION. REMAINING PINS ARE NUMBERED COUNTER CLOCKWISE. 5. XXX IN DRAWING NUMBER REPRESENTS PACKAGE SIZE VARIATION WHERE X1 IS PACKAGE WIDTH, X2 IS PACKAGE LENGTH AND X3 IS PACKAGE HEIGHT. 6.NO JEDEC REGISTRATION AS OF AUG.1999. micro SMD, 5 Bump Package (BPA05) NS Package Number BPA05A For Order Numbers, refer to Table 1 in the “Order Information” section of this document. The dimensions for X1, X2 and X3 are as given: X1 = 0.930 +/− 0.030mm X2 = 1.107 +/− 0.030mm X3 = 0.850 +/− 0.050mm 15 www.national.com LP2981 Micropower 100 mA Ultra Low-Dropout Regulator Notes LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: [email protected] www.national.com National Semiconductor Europe Fax: +49 (0) 180-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Asia Pacific Customer Response Group Tel: 65-2544466 Fax: 65-2504466 Email: [email protected] National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.