SNVS093G June   1999  – May 2015 LM2990

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics: -5 V and -5.2 V
    6. 6.6 Electrical Characteristics: -12 V and -15 V
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Fixed Output-Voltage Options
      2. 7.3.2 Low Dropout Voltage
      3. 7.3.3 Short Circuit Protection (Current Limit)
      4. 7.3.4 Thermal Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation with VOUT(TARGET) -5 V ≥ VIN > -26 V
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 -5 V Post Regulator for an Isolated Switching Power Supply
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 External Capacitors
          2. 8.2.1.2.2 Forcing The Output Positive
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Fixed or Adjustable Current Sink
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)(2)
MIN MAX UNIT
Input voltage –26 0.3 V
Power dissipation(3) Internally limited
Junction temperature (TJmax) 125 °C
Storage temperature, Tstg –65 150 °C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and specifications.
(3) The maximum power dissipation is a function of TJmax, RθJA, and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJmax − TA)/RθJA. 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. Please refer to Thermal Information for more details.

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000 V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.

6.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)(1)
MIN NOM MAX UNIT
Junction temperature (TJ) –40 125 °C
Input voltage (operational) –26 –6 V
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

6.4 Thermal Information

THERMAL METRIC(1) LM2990S LM2990T UNIT
TO-263 (KTT) TO-220 (NDE)
3 PINS 3 PINS
RθJA Junction-to-ambient thermal resistance, High-K 41.3 22.8 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 43 15.7
RθJB Junction-to-board thermal resistance 23.2 4.2
ψJT Junction-to-top characterization parameter 11.3 2.2
ψJB Junction-to-board characterization parameter 20.4 4.2
RθJC(bot) Junction-to-case (bottom) thermal resistance 0.5 0.7
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics: –5 V and –5.2 V

VIN = −5 V + VOUT(NOM)(1), IOUT = 1 A, COUT = 47 μF, unless otherwise specified. All limits apply for TJ = 25°C, unless otherwise indicated in the Test Conditions.
PARAMETER TEST CONDITIONS LM2990 –5V   LM2990 –5.2V   UNIT
MIN(2) TYP(3) MAX(2) MIN(2) TYP(3) MAX(2)
Output voltage (VOUT) 5 mA ≤ IOUT ≤ 1 A −5.1 –5 –4.9 −5.3 –5.2 –5.1 V
5 mA ≤ IOUT ≤ 1 A
−40°C ≤ TJ ≤ 125°C		 –5.25 –5 −4.75 –5.46 –5.2 –4.94 V
Line regulation IOUT = 5 mA,
VO(NOM) −1 V > VIN > −26 V		 4 40 4 40 mV
Load regulation 50 mA ≤ IOUT ≤ 1 A 1 40 1 40 mV
Dropout voltage IOUT = 0.1 A, ΔVOUT ≤ 100 mV
−40°C ≤ TJ ≤ 125°C		 0.1 0.3 0.1 0.3 V
IOUT = 1 A, ΔVOUT ≤ 100 mV
−40°C ≤ TJ ≤ 125°C		 0.6 1 0.6 1 V
Quiescent current (Iq) IOUT ≤ 1 A 1 5 1 5 mA
IOUT = 1 A, VIN = VOUT(NOM) 9 50 9 50
Short circuit current RL = 1 Ω(4) 1.5 1.8 1.5 1.8 A
Maximum output current See(4) 1.5 1.8 1.5 1.8 A
Ripple rejection Vripple = 1 Vrms,
ƒripple = 1 kHz, IOUT = 5 mA		 50 58 50 58 dB(min)
Output noise voltage 10 Hz to 100 kHz, IOUT = 5 mA 250 750 250 750 μV(max)
Long-term stability 1000 Hours 2000 2000 ppm
(1) VOUT(NOM) is the nominal (typical) regulator output voltage, −5 V, −5.2 V, −12 V or −15 V.
(2) Limits are specified and 100% production tested.
(3) Typicals are at TJ = 25°C and represent the most likely parametric norm.
(4) The short circuit current is less than the maximum output current with the −12 V and −15 V versions due to internal foldback current limiting. The −5 V and −5.2 V 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 1.5 A.

6.6 Electrical Characteristics: –12 V and –15 V

VIN = −5 V + VOUT(NOM)(1), IOUT = 1 A, COUT = 47 μF, unless otherwise specified. All limits apply for TJ = 25°C, unless otherwise indicated in the Test Conditions.
PARAMETER TEST CONDITIONS LM2990 –12V   LM2990 –15V   UNIT
MIN(2) TYP(3) MAX(2) MIN(2) TYP(3) MAX(2)
Output voltage (VOUT) 5 mA ≤ IOUT ≤ 1 A −12.24 –12 –11.76 −15.30 –15 –14.70 V
5 mA ≤ IOUT ≤ 1 A
−40°C ≤ TJ ≤ 125°C		 –12.60 –12 −11.40 –15.75 –15 –14.25 V
Line regulation IOUT = 5 mA,
VOUT(NOM) −1 V > VIN > −26 V		 6 60 6 60 mV
Load regulation 50 mA ≤ IOUT ≤ 1 A 3 50 3 50 mV
Dropout voltage IOUT = 0.1 A, ΔVOUT ≤ 100 mV
−40°C ≤ TJ ≤ 125°C		 0.1 0.3 0.1 0.3 V
IOUT = 1 A, ΔVOUT ≤ 100 mV
−40°C ≤ TJ ≤ 125°C		 0.6 1 0.6 1 V
Quiescent current (Iq) IOUT ≤ 1 A 1 5 1 5 mA
IOUT = 1 A, VIN = VOUT(NOM) 9 50 9 50
Short circuit current RL = 1 Ω(4) 0.9 1.2 0.75 1.2 A
Maximum output current See(4) 1.4 1.8 1.4 1.8 A
Ripple rejection Vripple = 1 Vrms,
ƒripple = 1 kHz, IOUT = 5 mA		 42 52 42 52 dB(min)
Output noise voltage 10 Hz to 100 kHz, IOUT = 5 mA 500 1500 500 1500 μV(max)
Long-term stability 1000 hours 2000 2000 ppm
(1) VOUT(NOM) is the nominal (typical) regulator output voltage, −5 V, −5.2 V, −12 V or −15 V.
(2) Limits are specified and 100% production tested.
(3) Typicals are at TJ = 25°C and represent the most likely parametric norm.
(4) The short circuit current is less than the maximum output current with the −12 V and −15 V versions due to internal foldback current limiting. The −5 V and −5.2 V 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 1.5 A.

6.7 Typical Characteristics

LM2990 1080114.png
Figure 1. Dropout Voltage
LM2990 1080116.png
Figure 3. LM2990-5.0 and LM2990-5.2 Quiescent Current
LM2990 1080118.png
Figure 5. LM2990-15 Quiescent Current
LM2990 1080120.png
Figure 7. LM2990-5 and LM2990-5.2 Line Transient Response
LM2990 1080122.png
Figure 9. LM2990-12 and LM2990-15 Low-Voltage Behavior
LM2990 1080124.png
Figure 11. LM2990-12 and LM2990-15 Load Transient Response
LM2990 1080126.png
Figure 13. LM2990-5 and LM2990-5.2 Output Impedance
LM2990 1080128.png
Figure 15. LM2990-12 and LM2990-15 Ripple Rejection
LM2990 1080130.png
Figure 17. Maximum Output Current
LM2990 1080132.png
The maximum power dissipation is a function of TJmax, RθJA, and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJmax − TA)/RθJA. 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. Please refer to Thermal Information for more details.
Figure 19. Maximum Power Dissipation (TO-263)
LM2990 1080115.png
Figure 2. Normalized Output Voltage
LM2990 1080117.png
Figure 4. LM2990-12 Quiescent Current
LM2990 1080119.png
Figure 6. LM2990-5 and LM2990-5.2 Low Voltage Behavior
LM2990 1080121.png
Figure 8. LM2990-5 and LM2990-5.2 Load Transient Response
LM2990 1080123.png
Figure 10. LM2990-12 and LM2990-15 Line Transient Response
LM2990 1080125.png
Figure 12. LM2990-5 and LM2990-5.2 Ripple Rejection
LM2990 1080127.png
Figure 14. Maximum Output Current
LM2990 1080129.png
Figure 16. LM2990-12 and LM2990-15 Output Impedance
LM2990 1080131.png
Figure 18. Maximum Power Dissipation (TO-220)