SNVS769J March   2000  – December 2014 LM2940-N , LM2940C

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 8 V)
    6. 6.6 Electrical Characteristics (9 V and 10 V)
    7. 6.7 Electrical Characteristics (12 V and 15 V)
    8. 6.8 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 Short-Circuit Current Limit
      2. 7.3.2 Overvoltage Shutdown (OVSD)
      3. 7.3.3 Thermal Shutdown (TSD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation with Enable Control
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 External Capacitors
          1. 8.2.2.1.1 Minimum Capacitance
          2. 8.2.2.1.2 ESR Limits
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
    3. 10.3 Heatsinking
      1. 10.3.1 Heatsinking TO-220 Package Parts
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Related Links
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • NDE|3
  • NDG|3
  • KTT|3
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings(1)(4)

MIN MAX UNIT
LM2940-N KTT, NDE, DCY ≤ 100 ms 60 V
LM2940C KTT, NDE ≤ 1 ms 45
Internal power dissipation(2) Internally Limited
Maximum junction temperature 150 °C
Soldering temperature(3)        TO-220 (NDE), Wave (10 s) 260
DDPAK/TO-263 (KTT) (30 s) 235
SOT-223 (DCY) (30 s) 260
WSON-8 (NGN) (30 s) 235
Storage temperature, Tstg −65 150
(1) Absolute Maximum Ratings are limits beyond which damage to the device may occur. Recommended Operating Conditions are conditions under which the device functions but the specifications might not be ensured. For ensured specifications and test conditions see the Electrical Characteristics (5 V and 8 V).
(2) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ, the junction-to-ambient thermal resistance, RθJA, and the ambient temperature, TA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. The value of R θJA (for devices in still air with no heatsink) is 23.3°C/W for the TO-220 package, 40.9°C/W for the DDPAK/TO-263 package, and 59.3°C/W for the SOT-223 package. The effective value of RθJA can be reduced by using a heatsink (see Heatsinking for specific information on heatsinking). The value of RθJA for the WSON package is specifically dependent on PCB trace area, trace material, and the number of layers and thermal vias. For improved thermal resistance and power dissipation for the WSON package, refer to Application Note AN-1187 Leadless Leadframe Package (LLP) (SNOA401). It is recommended that 6 vias be placed under the center pad to improve thermal performance.
(3) Refer to JEDEC J-STD-020C for surface mount device (SMD) package reflow profiles and conditions. Unless otherwise stated, the temperature and time are for Sn-Pb (STD) only.
(4) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and specifications.

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)
MIN MAX UNIT
Input voltage 6 26 V
Temperature          LM2940-N NDE, LM2940-N KTT −40 125 °C
LM2940C NDE, LM2940C KTT 0 125
LM2940-N DCY −40 85
LM2940-N NGN −40 125

6.4 Thermal Information

THERMAL METRIC(1) LM2940-N, LM2940C LM2940-N UNIT
TO-220 (NDE) DDPAK/TO-263 (KTT) SOT-223 (DCY) WSON (NGN)
3 PINS 3 PINS 4 PINS 8 PINS
RθJA Junction-to-ambient thermal resistance(2) 23.3  40.9  59.3  40.5  °C/W
RθJC(top) Junction-to-case (top) thermal resistance 16.1  43.5  38.9  26.2 
RθJB Junction-to-board thermal resistance 4.8  23.5  8.1  17.0 
ψJT Junction-to-top characterization parameter 2.7  10.3  1.7  0.2 
ψJB Junction-to-board characterization parameter 4.8  22.5  8.0  17.2 
RθJC(bot) Junction-to-case (bottom) thermal resistance 1.1  0.8  n/a  3.2 
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
(2) Thermal information for the TO-220 package is for a package vertically mounted with a heat sink in the middle of a PCB which is compliant to the JEDEC HIGH-K 2s2p (JESD51-7). The heatsink-to-ambient thermal resistance, RƟSA, is 21.7°C/W. See Heatsinking TO-220 Package Parts for more information.

6.5 Electrical Characteristics (5 V and 8 V)

Unless otherwise specified: VIN = VOUT + 5 V, IOUT = 1 A and COUT = 22 µF. MIN (minimum) and MAX (maximum) limits apply over the recommended operating temperature range, unless otherwise noted; typical limits apply for TA = TJ = 25°C.
PARAMETER TEST CONDITIONS 5 V 8 V UNIT
MIN TYP MAX MIN TYP MAX
Input voltage 5 mA ≤ IOUT ≤ 1 A 6.25 26 9.4 26 V
Output voltage 5 mA ≤ IOUT ≤ 1A 4.75 5 5.25 7.6 8 8.4
5 mA ≤ IOUT ≤ 1A, TJ = 25°C 4.85 5 5.15 7.76 8 8.24
Line regulation VOUT + 2 V ≤ VIN ≤ 26 V, IOUT = 5 mA
TJ = 25°C		 20 50 20 80 mV
Load regulation 50 mA ≤ IOUT ≤ 1 A LM2940-N 35 80 55 130 mV
50 mA ≤ IOUT ≤ 1 A
TJ = 25°C		 LM2940-N 35 50 55 80
LM2940C 35 50 55 80
Output impedance 100 mADC, 20 mArms, ƒOUT = 120 Hz 35 55 mΩ
Quiescent current VOUT + 2 V ≤ VIN ≤ 26 V,
IOUT = 5 mA		 LM2940-N 10 20 10 20 mA
VOUT + 2 V ≤ VIN ≤ 26 V,
IOUT = 5 mA
TJ = 25°C		 LM2940-N 10 15 10 15
LM2940C 10 15
VIN = VOUT + 5 V, IOUT = 1 A 30 60 30 60
VIN = VOUT + 5 V, IOUT = 1 A
TJ = 25°C		 30 45 30 45
Output noise voltage 10 Hz to 100 kHz, IOUT = 5 mA 150 240 µVrms
Ripple rejection ƒOUT = 120 Hz, 1 Vrms, IOUT = 100 mA LM2940-N 54 72 48 66 dB
ƒOUT = 120 Hz, 1 Vrms, IOUT = 100 mA
TJ = 25°C		 LM2940-N 60 72 54 66
LM2940C 60 72 54 66
Long-term stability 20 32 mV/1000 Hr
Dropout voltage IOUT = 1A 0.5 1 0.5 1 V
IOUT = 1A, TJ = 25°C 0.5 0.8 0.5 0.8
IOUT = 100 mA 110 200 110 200 mV
IOUT = 100 mA, TJ = 25°C 110 150 110 150
Short-circuit current See(1), TJ = 25°C 1.6 1.9 1.6 1.9 A
Maximum line transient ROUT = 100Ω, T ≤ 100 ms LM2940-N 60 75 60 75 V
ROUT = 100Ω, T ≤ 1 ms
TJ = 25°C		 LM2940C 45 55 45 555
Reverse polarity
DC input voltage		 ROUT = 100 Ω LM2940-N –15 –30 –15 –30 V
ROUT = 100 Ω
TJ = 25°C		 LM2940C –15 –30 –15 –30
Reverse polarity
Transient Input Voltage		 ROUT = 100 Ω, T ≤ 100 ms LM2940-N –50 –75 –50 –75 V
ROUT = 100 Ω, T ≤ 1 ms LM2940C –45 –55
(1) Output current will decrease with increasing temperature but will not drop below 1 A at the maximum specified temperature.

6.6 Electrical Characteristics (9 V and 10 V)

Unless otherwise specified: VIN = VOUT + 5 V, IOUT = 1 A and COUT = 22 µF. MIN (minimum) and MAX (maximum) limits apply over the recommended operating temperature range, unless otherwise noted; typical limits apply for TA = TJ = 25°C.
PARAMETER TEST CONDITIONS 9 V 10 V UNIT
MIN TYP MAX MIN TYP MAX
Input voltage 5 mA ≤ IOUT ≤ 1 A 10.5 26 11.5 26 V
Output voltage 5 mA ≤ IOUT ≤ 1A 8.55 9 9.45 9.5 10 10.5
5 mA ≤ IOUT ≤ 1A, TJ = 25°C 8.73 9 9.27 9.7 10 10.3
Line regulation VOUT + 2 V ≤ VIN ≤ 26 V, IOUT = 5 mA
TJ = 25°C		 20 90 20 100 mV
Load regulation 50 mA ≤ IOUT ≤ 1 A LM2940-N 60 150 65 165 mV
50 mA ≤ IOUT ≤ 1 A
TJ = 25°C		 LM2940-N 60 90 65 100
LM2940C 60 90
Output impedance 100 mADC, 20 mArms, ƒOUT = 120 Hz 60 65 mΩ
Quiescent current VOUT + 2 V ≤ VIN ≤ 26 V,
IOUT = 5 mA		 LM2940-N 10 20 10 20 mA
VOUT + 2 V ≤ VIN ≤ 26 V,
IOUT = 5 mA
TJ = 25°C		 LM2940-N 10 15 15
LM2940C 10 15
VIN = VOUT + 5 V, IOUT = 1 A 30 60 30 60
VIN = VOUT + 5 V, IOUT = 1 A
TJ = 25°C		 30 45 30 45
Output noise voltage 10 Hz to 100 kHz, IOUT = 5 mA 270 300 µVrms
Ripple rejection ƒOUT = 120 Hz, 1 Vrms
IOUT = 100 mA		 LM2940-N 46 64 45 63 dB
ƒOUT = 120 Hz, 1 Vrms
IOUT = 100 mA
TJ = 25°C		 LM2940-N 52 64 51 63
LM2940C 52 64
Long-term stability 34 36 mV/1000 Hr
Dropout voltage IOUT = 1A 0.5 1 0.5 1 V
IOUT = 1A, TJ = 25°C 0.5 0.8 0.5 0.8
IOUT = 100 mA 110 200 110 200 mV
IOUT = 100 mA, TJ = 25°C 110 150 110 150
Short-circuit current See(1), TJ = 25°C 1.6 1.9 1.6 1.9 A
Maximum line transient ROUT = 100Ω, T ≤ 100 ms LM2940-N 60 75 60 75 V
ROUT = 100Ω, T ≤ 100 ms
TJ = 25°C		 LM2940C 45 55
Reverse polarity
DC input voltage		 ROUT = 100 Ω LM2940-N –15 –30 –15 –30 V
ROUT = 100 Ω
TJ = 25°C		 LM2940C –15 –30
Reverse polarity
Transient Input Voltage		 ROUT = 100 Ω, T ≤ 100 ms LM2940-N –50 –75 –50 –75 V
LM2940C –45 –55

6.7 Electrical Characteristics (12 V and 15 V)

Unless otherwise specified: VIN = VOUT + 5 V, IOUT = 1 A and COUT = 22 µF. MIN (minimum) and MAX (maximum) limits apply over the recommended operating temperature range, unless otherwise noted; typical limits apply for TA = TJ = 25°C.
PARAMETER TEST CONDITIONS 12 V 15 V UNIT
MIN TYP MAX MIN TYP MAX
Input voltage 5 mA ≤ IOUT ≤ 1 A 13.6 26 16.75 26 V
Output voltage 5 mA ≤ IOUT ≤ 1A 11.40 12 12.6 14.25 15 15.75
5 mA ≤ IOUT ≤ 1A, TJ = 25°C 11.64 12 12.36 14.55 15 15.45
Line regulation VOUT + 2 V ≤ VIN ≤ 26 V, IOUT = 5 mA
TJ = 25°C		 20 120 20 150 mV
Load regulation 50 mA ≤ IOUT ≤ 1 A LM2940-N 55 200 mV
50 mA ≤ IOUT ≤ 1 A
TJ = 25°C		 LM2940-N 55 120
LM2940C 55 120 70 150
Output impedance 100 mADC, 20 mArms, ƒOUT = 120 Hz 80 100 mΩ
Quiescent current VOUT + 2 V ≤ VIN ≤ 26 V,
IOUT = 5 mA		 LM2940-N 10 20 mA
VOUT + 2 V ≤ VIN ≤ 26 V,
IOUT = 5 mA
TJ = 25°C		 LM2940-N 10 15
LM2940C 10 15 10 15
VIN = VOUT + 5 V, IOUT = 1 A 30 60 30 60
VIN = VOUT + 5 V, IOUT = 1 A
TJ = 25°C		 30 45 30 45
Output noise voltage 10 Hz to 100 kHz, IOUT = 5 mA 360 450 µVrms
Ripple rejection ƒOUT = 120 Hz, 1 Vrms, IOUT = 100 mA LM2940-N 48 66 dB
ƒOUT = 120 Hz, 1 Vrms, IOUT = 100 mA
TJ = 25°C		 LM2940-N 54 66
LM2940C 54 66 52 64
Long-term stability 48 60 mV/1000 Hr
Dropout voltage IOUT = 1A 0.5 1 0.5 1 V
IOUT = 1A, TJ = 25°C 0.5 0.8 0.5 0.8
IOUT = 100 mA 110 200 110 200 mV
IOUT = 100 mA, TJ = 25°C 110 150 110 150
Short-circuit current See(1), TJ = 25°C 1.6 1.9 1.6 1.9 A
Maximum line transient ROUT = 100Ω, T ≤ 100 ms LM2940-N 60 75 V
ROUT = 100Ω, T ≤ 100 ms
TJ = 25°C		 LM2940C 45 55 45 55
Reverse polarity
DC input voltage		 ROUT = 100 Ω LM2940-N –15 –30 V
ROUT = 100 Ω
TJ = 25°C		 LM2940C –15 –30 –15 –30
Reverse polarity
transient input voltage		 ROUT = 100 Ω, T ≤ 100 ms LM2940-N –50 –75 V
ROUT = 100 Ω, T ≤ 1 ms LM2940C –45 –55 –45 –55

6.8 Typical Characteristics

882213.pngFigure 1. Dropout Voltage
882215.pngFigure 3. Output Voltage vs. Temperature
882214.pngFigure 2. Dropout Voltage vs. Temperature
882216.pngFigure 4. Quiescent Current vs. Temperature
882217.pngFigure 5. Quiescent Current
882219.pngFigure 7. Line Transient Response
882221.pngFigure 9. Ripple Rejection
882227.pngFigure 11. Low Voltage Behavior
882229.pngFigure 13. Low Voltage Behavior
882231.pngFigure 15. Output at Voltage Extremes
882234.pngFigure 17. Output at Voltage Extremes
882236.pngFigure 19. Output at Voltage Extremes
882208.pngFigure 21. Peak Output Current
882223.pngFigure 23. Maximum Power Dissipation (TO-220)
882210.pngFigure 25. Maximum Power Dissipation (DDPAK/TO-263)
882218.pngFigure 6. Quiescent Current
882220.pngFigure 8. Load Transient Response
882226.pngFigure 10. Low Voltage Behavior
882228.pngFigure 12. Low Voltage Behavior
882230.pngFigure 14. Low Voltage Behavior
882233.pngFigure 16. Output at Voltage Extremes
882235.pngFigure 18. Output at Voltage Extremes
882206.pngFigure 20. Output Capacitor ESR
882222.pngFigure 22. Output Impedance
882224.pngFigure 24. Maximum Power Dissipation (SOT-223)