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Details, datasheet, quote on part number:LM2990
 
 
Part:LM2990
Category:Power Management => Regulators => Linear Voltage Regulators => LDO (Low Drop Out) => Negative Voltage->Fixed
Description:LM2990 - Negative Low Dropout Regulator, Package: Cerdip, Pin Nb=16
Company:National Semiconductor Corporation
Datasheet:Download LM2990 datasheet   File size : 431 kB
Request For quote:  Find where to buy LM2990
 



Datasheet text preview:
LM2990 Negative Low Dropout Regulator

June 1999

LM2990 Negative Low Dropout Regulator
General Description
The LM2990 is a three-terminal, low dropout, 1 ampere negative voltage regulator available with fixed output voltages of -5, -5.2, -12, and -15V. The LM2990 uses new circuit design techniques to provide low dropout and low quiescent current. The dropout voltage at 1A load current is typically 0.6V and a guaranteed worst-case maximum of 1V over the entire operating temperature range. The quiescent current is typically 1 mA with 1A load current and an input-output voltage differential greater than 3V. A unique circuit design of the internal bias supply limits the quiescent current to only 9 mA (typical) when the regulator is in the dropout mode (VOUT - VIN 3V). Output voltage accuracy is guaranteed to ± 5% over load, and temperature extremes. The LM2990 is short-circuit proof, and thermal shutdown includes hysteresis to enhance the reliability of the device when overloaded for an extended period of time. The LM2990 is available in a 3-lead TO-220 package and is rated for operation over the automotive temperature range of -40°C to +125°C.

Features
n n n n n n n 5% output accuracy over entire operating range Output current in excess of 1A Dropout voltage typically 0.6V at 1A load Low quiescent current Internal short circuit current limit Internal thermal shutdown with hysteresis Functional complement to the LM2940 series

Applications
n Post switcher regulator n Local, on-card, regulation n Battery operated equipment

Typical Application

DS010801-1

*Required if the regulator is located further than 6 inches from the power supply filter capacitors. A 1 µF solid tantalum or a 10 µF aluminum electrolytic capacitor is recommended. **Required for stability. Must be at least a 10 µF aluminum electrolytic or a 1 µF solid tantalum to maintain stability. May be increased without bound to maintain regulation during transients. Locate the capacitor as close as possible to the regulator. The equivalent series resistance (ESR) is critical, and should be less than 10 over the same operating temperature range as the regulator.

Ordering Information and Connection Diagrams
Temperature Range -40°C to +125°C -55°C to +125°C Output Voltage -5.0 LM2990T-5.0 LM2990S-5.0 LM2990J-5.0-QML 5962-9571101QEA LM2990WG5.0-QML 5962-9571101QXA -5.2 LM2990T-5.2 -12 LM2990T-12 LM2990S-12 LM2990J-12-QML 5962-9571001QEA -15 LM2990T-15 LM2990S-15 LM2990J-15-QML 5962-9570901QEA TO-220 TO-263 J16A WG16A Package

© 1999 National Semiconductor Corporation

DS010801

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Ordering Information and Connection Diagrams (Continued)
3-Lead TO-220

TO-263 Surface-Mount Package

DS010801-11

Top View
DS010801-2

Front View Order Number LM2990T-5.0, LM2990T-5.2, LM2990T-12 or LM2990T-15 See NS Package Number T03B

DS010801-12

Side View Order Number LM2990S-5.0, LM2990S-12 or LM2990S-15 See NS Package Number TS3B

16-Lead Ceramic Dual-in-Line Package

16-Lead Ceramic Surface Mount Package

DS010801-33

Top View Order Number LM2990J-5.0-QML (5962-9571101QEA), LM2990J-12-QML (5962-9571001QEA), or LM2990J-15-QML (5962-9570901QEA), See NS Package Number J16A

DS010801-34

Top View Order Number LM2990WG5.0-QML (5962-9571101QXEA) See NS Package Number WG16A

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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Input Voltage ESD Susceptibility (Note 2) Power Dissipation (Note 3) Junction Temperature (TJmax) -26V to +0.3V 2 kV Internally Limited 125°C

Storage Temperature Lead Temperature (Soldering, 10 sec.)

-65°C to +150°C 260°C

Operating Ratings(Note 1)
Junction Temperature Range (TJ) Maximum Input Voltage (Operational) -40°C to +125°C -26V

Electrical Characteristics
VIN = -5V + VO(NOM) (Note 6) , IO = 1A, CO = 47 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range, -40°C TJ 125°C, all other limits apply for TJ = 25°C. LM2990-5.0 Parameter Output Voltage (VO) Conditions 5 mA IO 1A -5 5 mA IO 1A Line Regulation Load Regulation Dropout Voltage Quiescent Current (Iq) Short Circuit Current Maximum Output Current Ripple Rejection Output Noise Voltage Long Term Stability IO = 5 mA, VO(NOM) -1V > VIN > -26V 50 mA IO 1A IO = 0.1A, VO 100 mV IO = 1A, VO 100 mV IO 1A IO = 1A, VIN = VO(NOM) RL = 1 (Note 7) (Note 7) Vripple = 1 Vrms, ripple = 1 kHz, IO = 5 mA 10 Hz­ 100 kHz, IO = 5 mA 1000 Hours 1 0.1 0.6 1 9 1.8 1.8 58 250 2000 40 0.3 1 5 50 1.5 1.5 50 750 1 0.1 0.6 1 9 1.8 1.8 58 250 2000 40 0.3 1 5 50 1.5 1.5 50 750 mV (max) V (max) V (max) mA (max) mA (max) A (min) A (min) dB (min) µV (max) ppm 4 -4.75 -5.25 40 4 Typ (Note 4) Limit (Note 5) -4.90 -5.10 -5.2 -4.94 -5.46 40 LM2990-5.2 Typ (Note 4) Limit (Note 5) -5.10 -5.30 V (max) mV (min) V V (max) V (min) mV (max) Units (Limit)

Electrical Characteristics
VIN = -5V + VO(NOM) (Note 6) , IO = 1A, CO = 47 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range, -40°C TJ 125°C, all other limits apply for TJ = 25°C. LM2990-12 Parameter Output Voltage (VO) Conditions 5 mA IO 1A -12 5 mA IO 1A Line Regulation Load Regulation Dropout Voltage Quiescent Current (Iq) IO = 5 mA, VO(NOM) -1V > VIN > -26V 50 mA IO 1A IO = 0.1A, VO 100 mV IO = 1A, VO 100 mV IO 1A IO = 1A, VIN = VO(NOM) 3 0.1 0.6 1 9 50 0.3 1 5 50 3 0.1 0.6 1 9 50 0.3 1 5 50 mV (max) V (max) V (max) mA (max) mA (max) 6 -11.40 -12.60 60 6 Typ (Note 4) Limit (Note 5) -11.76 -12.24 -15 -14.25 -15.75 60 LM2990-15 Typ (Note 4) Limit (Note 5) -14.70 -15.30 V (max) V (min) V V (max) V (min) mV (max) Units (Limit)

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Electrical Characteristics

(Continued)

VIN = -5V + VO(NOM) (Note 6) , IO = 1A, CO = 47 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range, -40°C TJ 125°C, all other limits apply for TJ = 25°C. LM2990-12 Parameter Short Circuit Current Maximum Output Current Ripple Rejection Output Noise Voltage Long Term Stability Conditions RL = 1 (Note 7) (Note 7) Vripple = 1 Vrms, ripple = 1 kHz, IO = 5 mA 10 Hz­ 100 kHz, IO = 5 mA 1000 Hours Typ (Note 4) 1.2 1.8 52 500 2000 Limit (Note 5) 0.9 1.4 42 1500 LM2990-15 Typ (Note 4) 1.0 1.8 52 600 2000 Limit (Note 5) 0.75 1.4 42 1800 A (min) A (min) dB (min) µV (max) ppm Units (Limit)

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: Human body model, 100 pF discharged through a 1.5 k resistor. Note 3: The maximum power dissipation is a function of TJmax, JA, and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJmax - TA)/JA. If this dissipation is exceeded, the die temperature will rise above 125°C, and the LM2990 will eventually go into thermal shutdown at a TJ of approximately 160°C. For the LM2990, the junction-to-ambient thermal resistance, is 53°C/W, 73°C/W for the TO-263, and the junction-to-case thermal resistance is 3°C. If the TO-263 package is used, the thermal resistance can be reduced by increasing the P.C. board copper area thermally connected to the package. Using 0.5 square inches of copper area, JA is 50°C/W; with 1 square inch of copper area, JA is 37°C/W; and with 1.6 or more square inches of copper area, JA is 32°C/W. Note 4: Typicals are at TJ = 25°C and represent the most likely parametric norm. Note 5: Limits are guaranteed and 100% production tested. Note 6: VO(NOM) is the nominal (typical) regulator output voltage, -5V, -5.2V, -12V or -15V. Note 7: The short circuit current is less than the maximum output current with the -12V and -15V versions due to internal foldback current limiting. The -5V and -5.2V versions, tested with a lower input voltage, does not reach the foldback current limit and therefore conducts a higher short circuit current level. If the LM2990 output is pulled above ground, the maximum allowed current sunk back into the LM2990 is 1.5A.

Definition of Terms
Dropout Voltage: The input-output voltage differential at which the circuit ceases to regulate against further reduction in input voltage. Measured when the output voltage has dropped 100 mV from the nominal value obtained at (VO + 5V) input, dropout voltage is dependent upon load current and junction temperature. Input Voltage: The DC voltage applied to the input terminals with respect to ground. Input-Output Differential: The voltage difference between the unregulated input voltage and the regulated output voltage for which the regulator will operate. Line Regulation: The change in output voltage for a change in the input voltage. The measurement is made under conditions of low dissipation or by using pulse techniques such that the average chip temperature is not significantly affected. Load Regulation: The change in output voltage for a change in load current at constant chip temperature. Long Term Stability: Output voltage stability under accellerated life-test conditions after 1000 hours with maximum rated voltage and junction temperature. Output Noise Voltage: The rms AC voltage at the output, with constant load and no input ripple, measured over a specified frequency range. Quiescent Current: That part of the positive input current that does not contribute to the positive load current. The regulator ground lead current. Ripple Rejection: The ratio of the peak-to-peak input ripple voltage to the peak-to-peak output ripple voltage. Temperature Stability of VO: The percentage change in output voltage for a thermal variation from room temperature to either temperature extreme.

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Typical Performance Characteristics
Dropout Voltage Normalized Output Voltage LM2990-5.0 and LM2990-5.2 Quiescent Current

DS010801-14

DS010801-15 DS010801-16

LM2990-12 Quiescent Current

LM2990-15 Quiescent Current

LM2990-5 and LM2990-5.2 Low Voltage Behavior

DS010801-17

DS010801-18

DS010801-19

LM2990-5 and LM2990-5.2 Line Transient Response

LM2990-5 and LM2990-5.2 Load Transient Response

LM2990-12 and LM2990-15 Low Voltage Behavior

DS010801-20

DS010801-21

DS010801-22

LM2990-12 and LM2990-15 Line Transient Response

LM2990-12 and LM2990-15 Load Transient Response

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DS010801-24

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