SNVS770I June   1999  – January 2015 LM2941 , LM2941C

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: LM2941T, LM2941S, LM2941LD
    6. 6.6 Electrical Characteristics: LM2941CT, LM2941CS
    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 Short-Circuit Current Limit
      2. 7.3.2 Overvoltage Shutdown (OVSD)
      3. 7.3.3 Thermal Shutdown (TSD)
      4. 7.3.4 Thermal Overload Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation With ON/OFF 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 Output Capacitor
        2. 8.2.2.2 Setting the Output Voltage
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Power Dissipation
    4. 10.4 Thermal Considerations
      1. 10.4.1 TO-263 Mounting
      2. 10.4.2 WSON Mounting
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Definition of Terms
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • NDH|5
  • NEB|5
  • KTT|5
  • KC|5
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings(1)(2)

MIN MAX UNIT
Input voltage (Survival Voltage, ≤ 100 ms) LM2941T, LM2941S, LM2941LD 60 V
LM2941CT, LM2941CS 45 V
Internal power dissipation (3) Internally Limited
Maximum junction temperature 150 °C
Soldering remperature(4) TO-220 (T), Wave, 10 s 260 °C
TO-263 (S), 30 s 235 °C
WSON-8 (LD), 30 s 235 °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 TJ(max), RθJA, and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(max) − TA)/RθJA. If this dissipation is exceeded, the die temperature will rise above 150°C and the LM2941 will go into thermal shutdown. If the TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally connected to the package. The value 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 (SNOA401). It is recommended that 6 vias be placed under the center pad to improve thermal performance.
(4) 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.

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

MIN MAX UNIT
Temperatures LM2941T −40 125 °C
LM2941CT 0 125
LM2941S −40 125
LM2941CS 0 125
LM2941LD −40 125

6.4 Thermal Information

THERMAL METRIC(1)(3) LM2941LD LM2941S, LM2941T UNIT
WSON (NGN) TO-263 (KTT) TO-220 (KC)
8 PINS 5 PINS 5 PINS
RθJA Junction-to-ambient thermal resistance 40.5 41 32.1 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 26.2 43.2 25.6
RθJB Junction-to-board thermal resistance 17 22.9 18.3
ψJT Junction-to-top characterization parameter 0.2 11.4 8.5
ψJB Junction-to-board characterization parameter 17.2 21.9 17.7
RθJC(bot) Junction-to-case (bottom) thermal resistance 3.2 0.9 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: LM2941T, LM2941S, LM2941LD

5 V ≤ VOUT ≤ 20 V, VIN = VOUT + 5 V, COUT = 22 μF, unless otherwise specified. MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature Range (unless otherwise specified) and typical values apply at TJ = 25°C.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Reference voltage 5 mA ≤ IOUT ≤ 1 A(1) 1.211 1.275 1.339 V
5 mA ≤ IOUT ≤ 1 A(1), TJ = 25°C 1.237 1.275 1.313
Line regulation VOUT + 2 V ≤ VIN ≤ 26 V, IOUT = 5 mA 4 10 mV/V
Load regulation 50 mA ≤ IOUT ≤ 1 A 7 10 mV/V
Output impedance 100 mADC and 20 mArms, ƒOUT = 120 Hz 7 mΩ/V
Quiescent current VOUT + 2 V ≤ VIN < 26 V, IOUT = 5 mA 10 20 mA
VOUT + 2 V ≤ VIN < 26 V, IOUT = 5 mA, TJ = 25°C 10 15
VIN = VOUT + 5 V, IOUT = 1 A 30 60 mA
VIN = VOUT + 5 V, IOUT = 1 A, TJ = 25°C 30 45
RMS output noise, % of VOUT 10 Hz to 100 kHz, IOUT = 5 mA 0.003%
Ripple rejection ƒOUT = 120 Hz, 1 Vrms, IL = 100 mA 0.005 0.04 %/V
ƒOUT = 120 Hz, 1 Vrms, IL = 100 mA, TJ = 25°C 0.005 0.02
Long-term stability 0.4 %/1000 Hr
Dropout voltage IOUT = 1 A 0.5 1 V
IOUT = 1 A, TJ = 25°C 0.5 0.8
IOUT = 100 mA 110 200 mV
Short-circuit current VIN max = 26 V(2) 1.6 1.9 A
Maximum line transient VOUT max 1 V above nominal VOUT
ROUT = 100 Ω, t ≤ 100 ms		 60 75 V
Maximum operational input voltage 26 31 VDC
Reverse polarity
DC input voltage		 ROUT = 100 Ω, VOUT ≥ −0.6 V −15 −30 V
Reverse polarity
transient input voltage		 t ≤ 100 ms, ROUT = 100 Ω −50 −75
ON/OFF threshold
voltage ON		 IOUT ≤ 1 A 1.30 0.80 V
ON/OFF threshold
voltage OFF		 IOUT ≤ 1 A 2 1.3
ON/OFF threshold
current		 VON/OFF = 2 V, IOUT ≤ 1 A 50 300 μA
VON/OFF = 2 V, IOUT ≤ 1 A, TJ = 25°C 50 100
(1) The output voltage range is 5 V to 20 V and is determined by the two external resistors, R1 and R2. See Figure 18.
(2) Output current capability will decrease with increasing temperature, but will not go below 1 A at the maximum specified temperatures.

6.6 Electrical Characteristics: LM2941CT, LM2941CS

5 V ≤ VOUT ≤ 20 V, VIN = VOUT + 5 V, COUT = 22 μF, unless otherwise specified. MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature Range (unless otherwise specified) and typical values apply at TJ = 25°C.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Reference voltage 5 mA ≤ IOUT ≤ 1 A(1) 1.211 1.275 1.339 V
5 mA ≤ IOUT ≤ 1 A(1), TJ = 25°C 1.237 1.275 1.313
Line regulation VOUT + 2 V ≤ VIN ≤ 26 V, IOUT = 5 mA, TJ = 25°C 4 10 mV/V
Load regulation 50 mA ≤ IOUT ≤ 1 A, TJ = 25°C 7 10 mV/V
Output impedance 100 mADC and 20 mArms, ƒOUT = 120 Hz 7 mΩ/V
Quiescent current VOUT + 2 V ≤ VIN < 26 V, IOUT = 5 mA, TJ = 25°C 10 15 mA
VIN = VOUT + 5 V, IOUT = 1 A 30 60 mA
VIN = VOUT + 5 V, IOUT = 1 A, TJ = 25°C 30 45
RMS output noise, % of VOUT 10 Hz to 100 kHz
IOUT = 5 mA		 0.003%
Ripple rejection ƒOUT = 120Hz, 1 Vrms, IL = 100 mA, TJ = 25°C 0.005 0.02 %/V
Long-term stability 0.4 %/1000 Hr
Dropout voltage IOUT = 1A 0.5 1 V
IOUT = 1A, TJ = 25°C 0.5 0.8
IOUT = 100 mA 110 200 mV
Short-circuit current VIN max = 26 V(2), TJ = 25°C 1.6 1.9 A
Maximum line transient VOUT max 1 V above nominal VOUT, ROUT = 100 Ω, t ≤ 100 ms, , TJ = 25°C 45 55 V
Maximum operational input voltage TJ = 25°C 26 31 VDC
Reverse polarity
DC input voltage		 ROUT = 100 Ω, VOUT ≥ −0.6 V, TJ = 25°C −15 −30 V
Reverse polarity
transient input voltage		 t ≤ 100 ms, ROUT = 100 Ω, TJ = 25°C −45 −55
ON/OFF threshold
voltage ON		 IOUT ≤ 1 A, TJ = 25°C 1.3 0.8 V
ON/OFF threshold
voltage OFF		 IOUT ≤ 1 A, TJ = 25°C 2 1.3
ON/OFF threshold
current		 VON/OFF = 2 V, IOUT ≤ 1 A, TJ = 25°C 50 100 μA
(1) The output voltage range is 5 V to 20 V and is determined by the two external resistors, R1 and R2. See Typical Application.
(2) Output current capability will decrease with increasing temperature, but will not go below 1 A at the maximum specified temperatures.

6.7 Typical Characteristics

882311.png
Figure 1. Dropout Voltage
882313.png
Figure 3. Output Voltage
882315.png
Figure 5. Quiescent Current
882317.png
Figure 7. Line Transient Response
882319.png
Figure 9. Ripple Rejection
882321.png
Figure 11. Low Voltage Behavior
882323.png
Figure 13. Output Capacitor ESR
882325.png
Figure 15. Output at Voltage Extremes
882327.png
Figure 17. Maximum Power Dissipation (TO-220)
882312.png
Figure 2. Dropout Voltage vs. Temperature
882314.png
Figure 4. Quiescent Current vs. Temperature
882316.png
Figure 6. Quiescent Current
882318.png
Figure 8. Load Transient Response
882320.png
Figure 10. Output Impedance
882322.png
Figure 12. Low Voltage Behavior
882324.png
Figure 14. Output at Voltage Extremes
882326.png
Figure 16. Peak Output Current