View NSC05143_994126.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

LP2981 Micropower SOT, 100 mA Ultra Low-Dropout Regulator
May 1999
LP2981 Micropower SOT, 100 mA Ultra Low-Dropout Regulator
General Description
The LP2981 is a 100 mA, fixed-output voltage regulator designed specifically to meet the requirements of battery-powered applications. Using an optimized VIPTM (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 A @ 100 mA load, and 80 A @ 1 mA load. Sleep Mode. Less than 1 A quiescent current when ON/ OFF pin is pulled low. Smallest Possible Size. SOT-23 package uses an absolute minimum of 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.
Features
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 Package) < 1 A 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 -40C to +125C 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
VIPTM is a trademark of National Semiconductor Corporation.
(c) 1999 National Semiconductor Corporation
DS012506
www.national.com
Connection Diagram
5-Lead Small Outline Package (M5)
DS012506-3
Actual Size
DS012506-2
Top View For Ordering Information See Table 1 See NS Package Number MA05B
Ordering Information
TABLE 1. Package Marking and Order Information Output Voltage (V) 2.5 2.5 2.5 2.5 2.7 2.7 2.7 2.7 2.8 2.8 2.8 2.8 2.9 2.9 2.9 2.9 3.0 3.0 3.0 3.0 3.1 3.1 3.1 3.1 3.2 3.2 3.2 3.2 3.3 3.3 3.3 3.3 A A STD STD A A STD STD A A STD STD A A STD STD A A STD STD A A STD STD A A STD STD A A STD STD LP2981AIM5X-2.5 LP2981AIM5-2.5 LP2981IM5X-2.5 LP2981IM5-2.5 LP2981AIM5X-2.7 LP2981AIM5-2.7 LP2981IM5X-2.7 LP2981IM5-2.7 LP2981AIM5X-2.8 LP2981AIM5-2.8 LP2981IM5X-2.8 LP2981IM5-2.8 LP2981AIM5X-2.9 LP2981AIM5-2.9 LP2981IM5X-2.9 LP2981IM5-2.9 LP2981AIM5X-3.0 LP2981AIM5-3.0 LP2981IM5X-3.0 LP2981IM5-3.0 LP2981AIM5X-3.1 LP2981AIM5-3.1 LP2981IM5X-3.1 LP2981IM5-3.1 LP2981AIM5X-3.2 LP2981AIM5-3.2 LP2981IM5X-3.2 LP2981IM5-3.2 LP2981AIM5X-3.3 LP2981AIM5-3.3 LP2981IM5X-3.3 LP2981IM5-3.3 L0CA L0CA L0CB L0CB L0DA L0DA L0DB L0DB L77A L77A L77B L77B L0VA L0VA L0VB L0VB L05A L05A L05B L05B L38A L38A L38B L38B L35A L35A L35B L35B L04A L04A L04B L04B 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel Grade Order Information Package Marking Supplied as:
www.national.com
2
Ordering Information
Output Voltage (V) 3.6 3.6 3.6 3.6 3.8 3.8 3.8 3.8 4.0 4.0 4.0 4.0 4.7 4.7 4.7 4.7 5.0 5.0 5.0 5.0 A A STD STD A A STD STD A A STD STD A A STD STD A A STD STD Grade
(Continued)
TABLE 1. Package Marking and Order Information (Continued) Order Information LP2981AIM5X-3.6 LP2981AIM5-3.6 LP2981IM5X-3.6 LP2981IM5-3.6 LP2981AIM5X-3.8 LP2981AIM5-3.8 LP2981IM5X-3.8 LP2981IM5-3.8 LP2981AIM5X-4.0 LP2981AIM5-4.0 LP2981IM5X-4.0 LP2981IM5-4.0 LP2981AIM5X-4.7 LP2981AIM5-4.7 LP2981IM5X-4.7 LP2981IM5-4.7 LP2981AIM5X-5.0 LP2981AIM5-5.0 LP2981IM5X-5.0 LP2981IM5-5.0 Package Marking L0JA L0JA L0JB L0JB L36A L36A L36B L36B L0ZA L0ZA L0ZB L0ZB L0GA L0GA L0GB L0GB L03A L03A L03B L03B Supplied as: 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel 3k Units on Tape and Reel 250 Units on Tape and Reel
3
www.national.com
Absolute Maximum Ratings (Note 1)
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) -65C to +150C -40C to +125C 260C 2 kV
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))
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
Electrical Characteristics
Limits in standard typeface are for TJ = 25C, and limits in boldface type applyover the full operating temperature range. Unless otherwise specified: VIN = VO(NOM) + 1V, CIN = 1 F, IL = 1 mA, COUT = 4.7 F,VON/OFF = 2V. Symbol Parameter Conditions Typ LP2981AI-XX (Note 6) Min VO Output Voltage Tolerance IL = 1mA 1 mA < IL < 100 mA Output Voltage Line Regulation VIN-VO Dropout Voltage (Note 7) IL = 1 mA IL = 25 mA IL = 100 mA IGND Ground Pin Current IL = 0 IL = 1 mA IL = 25 mA IL = 100 mA VON/OFF < 0.3V VON/OFF ION/OFF IO(PK) en ON/OFF Input Voltage (Note 8) ON/OFF Input Current Peak Output Current Output Noise Voltage (RMS) Ripple Rejection VON/OFF < 0.15V High = O/P ON Low = O/P OFF VON/OFF = 0 VON/OFF = 5V VOUT VO(NOM) - 5% BW = 300 Hz-50 kHz, COUT = 10 F f = 1 kHz COUT = 10 F IO(MAX) Short Circuit Current RL = 0 (Steady State) (Note 9) 150 mA 7 70 200 65 80 200 600 0.01 0.05 1.4 0.50 0.01 5 400 160 63 150 1.6 0.15 -1 15 150 VO(NOM) + 1V VIN 16V IL = 0 1 0.007 -0.75 -1.0 -2.5 Max 0.75 1.0 2.5 0.014 0.032 3 5 10 15 100 150 250 375 95 125 110 170 300 550 800 1500 0.8 2 1.6 0.15 -1 15 mA V dB A LP2981I-XX (Note 6) Min -1.25 -2.0 -3.5 Max 1.25 2.0 3.5 0.014 0.032 3 5 10 15 100 150 250 375 95 125 110 170 300 550 800 1500 0.8 2 V A mV %/V %VNOM Units
www.national.com
4
Electrical Characteristics
Note 2: The ESD rating of pins 3 and 4 is 1 kV.
(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 3: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal resistance, JA, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated using:
The value of JA for the SOT-23 package is 220C/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 25C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control (SQC) methods. The limits are used to calculate National's Averaging Outgoing 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
Typical Performance Characteristics Unless otherwise specified: TA = 25C, VIN = VO(NOM) + 1V, COUT = 4.7 F, CIN = 1 F all voltage options, ON/OFF pin tied to VIN.
Output Voltage vs Temperature Output Voltage vs Temperature
DS012506-6
DS012506-7
Output Voltage vs Temperature
Dropout Characteristics
DS012506-9 DS012506-8
Dropout Characteristics
Dropout Characteristics
DS012506-10
DS012506-11
www.national.com
6
Typical Performance Characteristics Unless otherwise specified: TA = 25C, VIN = VO(NOM) + 1V, COUT = 4.7 F, CIN = 1 F all voltage options, ON/OFF pin tied to VIN. (Continued)
Dropout Voltage vs Temperature Dropout Voltage vs Load Current
DS012506-12
DS012506-13
Ground Pin Current vs Temperature
Ground Pin Current vs Load Current
DS012506-14
DS012506-15
Input Current vs VIN
Input Current vs VIN
DS012506-16
DS012506-17
7
www.national.com
Typical Performance Characteristics Unless otherwise specified: TA = 25C, VIN = VO(NOM) + 1V, COUT = 4.7 F, CIN = 1 F all voltage options, ON/OFF pin tied to VIN. (Continued)
Line Transient Response Line Transient Response
DS012506-18
DS012506-19
Load Transient Response
Load Transient Response
DS012506-20
DS012506-21
Load Transient Response
Load Transient Response
DS012506-22
DS012506-23
www.national.com
8
Typical Performance Characteristics Unless otherwise specified: TA = 25C, VIN = VO(NOM) + 1V, COUT = 4.7 F, CIN = 1 F 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
Typical Performance Characteristics Unless otherwise specified: TA = 25C, VIN = VO(NOM) + 1V, COUT = 4.7 F, CIN = 1 F 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
DS012506-33
Turn-On Waveform
Turn-Off Waveform
DS012506-34
DS012506-35
www.national.com
10
Typical Performance Characteristics Unless otherwise specified: TA = 25C, VIN = VO(NOM) + 1V, COUT = 4.7 F, CIN = 1 F all voltage options, ON/OFF pin tied to VIN. (Continued)
ON/OFF Pin Current vs VON/OFF ON/OFF Threshold vs Temperature
DS012506-36
DS012506-37
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 F 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).
11
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 F ceramic was measured and found to have an ESR of about 15 m, which is low enough to cause oscillations. If a ceramic capacitor is used on the output, a 1 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 20C to -40C. Also, some aluminum electrolytics are not operational below -25C because the electrolyte can freeze.
DS012506-38
FIGURE 1. 5V/3.3 F ESR Curves
www.national.com
Application Hints
(Continued)
REVERSE CURRENT PATH The power transistor used in the LP2981 has an inherent diode connected between the regulator input and output (see below).
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 F ESR Curves
DS012506-43
DS012506-40
FIGURE 3. 3V/3.3 F ESR Curves
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/s. Important: the regulator shutdown function will operate incorrectly if a slow-moving signal is applied to the ON/OFF input.
DS012506-42
FIGURE 4. 3V/10 F ESR Curves
www.national.com
12
LP2981 Micropower SOT, 100 mA Ultra Low-Dropout Regulator
Physical Dimensions
inches (millimeters) unless otherwise noted
5-Lead Small Outline Package (M5) NS Package Number MA05B For Order Numbers, refer to Table 1 in the "Ordering Information" section of this document.
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: support@nsc.com www.national.com National Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 1 80-530 85 85 English Tel: +49 (0) 1 80-532 78 32 Francais Tel: +49 (0) 1 80-532 93 58 Italiano Tel: +49 (0) 1 80-534 16 80
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: sea.support@nsc.com
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.

▲Up To Search▲

Price & Availability of NSC05143

	To Download NSC05143 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .