SNVS764Q January   2000  – December 2017 LP2950-N , LP2951-N

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Voltage Options
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information: LP2950-N
    5. 7.5 Thermal Information: LP2951-N
    6. 7.6 Electrical Characteristics
    7. 7.7 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Fixed Voltage Options and Programmable Voltage Version
      2. 8.3.2 High Accuracy Output Voltage
      3. 8.3.3 Low Dropout Voltage
      4. 8.3.4 Shutdown Mode
      5. 8.3.5 Error Detection Comparator Output
      6. 8.3.6 Internal Protection Circuitry
        1. 8.3.6.1 Short-Circuit Protection (Current Limit)
        2. 8.3.6.2 Thermal Protection
      7. 8.3.7 Enhanced Stability
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation with 30 V ≥ VIN > VOUT(TARGET) + 1 V
      2. 8.4.2 Operation with Shutdown Control
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1  1-A Regulator with 1.2-V Dropout
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Output Capacitor Requirements
          2. 9.2.1.2.2 Input Capacitor Requirements
          3. 9.2.1.2.3 Error Detection Comparator Output
          4. 9.2.1.2.4 Programming the Output Voltage (LP2951-N)
          5. 9.2.1.2.5 Reducing Output Noise
        3. 9.2.1.3 Application Curves
      2. 9.2.2  300-mA Regulator with 0.75-V Dropout
      3. 9.2.3  Wide Input Voltage Range Current Limiter
      4. 9.2.4  Low Drift Current Source
      5. 9.2.5  5-V Current Limiter
      6. 9.2.6  Regulator with Early Warning and Auxiliary Output
      7. 9.2.7  Latch Off When Error Flag Occurs
      8. 9.2.8  2-A Low Dropout Regulator
      9. 9.2.9  5-V Regulator with 2.5-V Sleep Function
      10. 9.2.10 Open Circuit Detector for 4 → 20-mA Current Loop
      11. 9.2.11 Regulator with State-of-Charge Indicator
      12. 9.2.12 Low Battery Disconnect
      13. 9.2.13 System Overtemperature Protection Circuit
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 WSON Mounting
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Related Links
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Specifications

Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)(1)
MIN MAX UNIT
Input supply voltage - SHUTDOWN input voltage error comparator output voltage(2) –0.3 30 V
FEEDBACK input voltage(2)(3) –1.5 30 V
Power dissipation Internally Limited
Junction temperature, TJ 150 °C
Soldering dwell time, temperature Wave 4 seconds, 260
Infrared 10 seconds, 240
Vapor phase 75 seconds, 219
Storage temperature, Tstg –65 150 °C
If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/Distributors for availability and specifications.
May exceed input supply voltage.
When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the output voltage should be diode-clamped to ground.

ESD Ratings

VALUE UNIT
LP2950-N
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2500 V
LP2951-N
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) IN, OUT, GND, ERROR ±2500 V
SHUTDOWN ±2000
SENSE ±1500
VTAP, FEEDBACK ±1000
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.

Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Maximum input supply voltage 30 V
Junction temperature, TJ(2) LP2950AC-XX, LP2950C-XX –40 125 °C
LP2951 –55 150 °C
LP2951AC-XX, LP2951C-XX –40 125 °C
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.
The junction-to-ambient thermal resistances are as follows: 157.4°C/W for the TO-92 (LP) package, 51.3°C/W for the TO-252 (NDP) package, 56.3°C/W for the molded PDIP (P), 117.7°C/W for the molded plastic SOIC (D), 171°C/W for the molded plastic VSSOP (DGK). The above thermal resistances for the P, D, and DGK packages apply when the package is soldered directly to the PCB. The value of RθJA for the WSON (NGT) package is typically 43.3°C/W but is dependent on the PCB trace area, trace material, and the number of layers and thermal vias. For details of thermal resistance and power dissipation for the WSON package, see AN-1187 Leadless Leadframe Package (LLP).

Thermal Information: LP2950-N

THERMAL METRIC(1) LP2950-N UNIT
LP (TO-92) NDP (TO-252)
3 PINS 3 PINS
RθJA(2) Junction-to-ambient thermal resistance, High-K 157.4 51.3(3) °C/W
RθJC(top) Junction-to-case (top) thermal resistance 81.2 53.5 °C/W
RθJB Junction-to-board thermal resistance 153.6 30.4 °C/W
ψJT Junction-to-top characterization parameter 25.2 5.5 °C/W
ψJB Junction-to-board characterization parameter n/a 30 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance n/a 2.2 °C/W
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.
Thermal resistance value RθJA is based on the EIA/JEDEC High-K printed circuit board defined by JESD51-7 - High Effective Thermal Conductivity Test Board for Leaded Surface Mount Packages.
The PCB for the TO-252 (NDP) package RθJA includes twelve (12) thermal vias under the tab per EIA/JEDEC JESD51-5.

Thermal Information: LP2951-N

THERMAL METRIC(1) LP2951-N UNIT
P (PDIP) D (SOIC) DGK (VSSOP) NGT (WSON)
8 PINS 8 PINS 8 PINS 8 PINS
RθJA(2) Junction-to-ambient thermal resistance, High K 56.3 117.7 171.0 43.3(3) °C/W
RθJC(top) Junction-to-case (top) thermal resistance 45.7 63.7 62.3 35.0 °C/W
RθJB Junction-to-board thermal resistance 33.5 57.9 91.4 23.3 °C/W
ψJT Junction-to-top characterization parameter 22.9 15.9 8.9 0.5 °C/W
ψJB Junction-to-board characterization parameter 33.3 57.5 90.1 20.5 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance n/a n/a n/a 9.1 °C/W
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.
Thermal resistance value RθJA is based on the EIA/JEDEC High-K printed circuit board defined by JESD51-7 - High Effective Thermal Conductivity Test Board for Leaded Surface Mount Packages.
The PCB for the WSON (NGT) package RθJA includes six (6) thermal vias under the exposed thermal pad per EIA/JEDEC JESD51-5.

Electrical Characteristics

over operating free-air temperature range (unless otherwise noted)(1)
PARAMETER TEST CONDITIONS(1) LP2951(2) LP2950AC-XX
LP2951AC-XX
LP2950C-XX
LP2951C-XX
UNIT
MIN TYP MAX MIN TYP MAX MIN TYP MAX
3-V VERSIONS(3)
Output voltage TJ = 25°C 2.985 3 3.015 2.985 3 3.015 2.970 3 3.030 V(4)
−25°C ≤ TJ ≤ 85°C 2.970 3 3.030 2.955 3 3.045 V(5)
Full operating temperature range 2.964 3 3.036 V(4)
2.964 3 3.036 2.940 3 3.060 V(5)
Output voltage 100 µA ≤ IL ≤ 100 mA,
100 µA ≤ IL ≤ 100 mA,
TJ ≤ TJMAX
2.955 3 3.045 V(4)
2.958 3 3.042 2.928 3 3.072 V(5)
3.3-V VERSIONS(3)
Output voltage TJ = 25°C 3.284 3.3 3.317 3.284 3.3 3.317 3.267 3.3 3.333 V(4)
−25°C ≤ TJ ≤ 85°C 3.3 3.267 3.3 3.333 3.251 3.3 3.350 V(5)
Full operating temperature range 3.260 3.3 3.340 V(4)
3.260 3.3 3.340 3.234 3.3 3.366 V(5)
Output voltage 100 µA ≤ IL ≤ 100 mA, TJ ≤ TJMAX 3.251 3.3 3.350 V(4)
3.254 3.3 3.346 3.221 3.3 3.379 V(5)
5-V VERSIONS(3)
Output voltage TJ = 25°C 4.975 5 5.025 4.975 5 5.025 4.95 5 5.05 V(4)
−25°C ≤ TJ ≤ 85°C 5 4.95 5 5.05 4.925 5 5.075 V(5)
Full operating temperature range 4.94 5 5.06 V(4)
4.94 5 5.06 4.9 5 5.1 V(5)
Output voltage 100 µA ≤ IL ≤ 100 mA, TJ ≤ TJMAX 4.925 5 5.075 V(4)
4.925 5 5.075 4.88 5 5.12 V(5)
ALL VOLTAGE OPTIONS
Output voltage temperature coefficient See(6), –40°C ≤ TJ ≤ 125°C 20 120 ppm/°C(4)
20 100 50 150 ppm/°C(5)
Line regulation(7) (VONOM + 1 V) ≤ Vin ≤ 30 V(8) 0.03% 0.1% 0.03% 0.11% 0.04% 0.2% See(4)
(VONOM + 1 V) ≤ Vin ≤ 30 V(8), –40°C ≤ TJ ≤ 125°C 0.03% 0.5% See(4)
0.03% 0.2% 0.04% 0.4% (5)
Load regulation(7) 100 µA ≤ IL ≤ 100 mA 0.04% 0.1% 0.04% 0.1% 0.1% 0.2% See(4)
100 µA ≤ IL ≤ 100 mA, –40°C ≤ TJ ≤ 125°C 0.04% 0.3% See(4)
0.04% 0.2% 0.1% 0.3% See(5)
Dropout voltage(9) IL = 100 µA 50 80 50 80 50 80 mV(4)
IL = 100 µA, –40°C ≤ TJ ≤ 125°C 150 mV(4)
150 150 mV(5)
IL = 100 mA 380 450 380 450 380 450 mV(4)
IL = 100 mA, –40°C ≤ TJ ≤ 125°C 600 600 600 mV(4)
600 600 mV(5)
Ground current IL = 100 µA 75 120 75 120 75 120 µA(4)
IL = 100 µA, –40°C ≤ TJ ≤ 125°C 140 µA(4)
140 140 µA(5)
IL = 100 mA 8 12 8 12 8 12 mA(4)
IL = 100 mA, –40°C ≤ TJ ≤ 125°C 14 mA(4)
14 14 mA(5)
Dropout ground current VIN = (VONOM − 0.5)V, IL = 100 µA 110 170 110 170 110 170 µA(4)
VIN = (VONOM − 0.5 V), IL = 100 µA, –40°C ≤ TJ ≤ 125°C 200 200 200 µA(4)
200 200 µA(5)
Current limit VOUT = 0 V 160 200 160 200 160 200 mA(4)
VOUT = 0 V, –40°C ≤ TJ ≤ 125°C 220 mA(4)
220 220 mA(5)
Thermal regulation See(10) 0.05 0.2 0.05 0.2 0.05 0.2 %/W(4)
Output noise
10 Hz to 100 kHz
CL = 1µF (5 V Only) 430 430 430 µVRMS
CL = 200 µF 160 160 160 µVRMS
CL = 3.3 µF
(Bypass = 0.01 µF
Pins 7 to 1 (LP2951-N)
100 100 100 µVRMS
8-PIN VERSIONS ONLY LP2951 LP2951AC-XX LP2951C-XX
Reference voltage 1.22 1.235 1.25 1.22 1.235 1.25 1.21 1.235 1.26 V(4)
–40°C ≤ TJ ≤ 125°C 1.2 1.26 V(4)
1.2 1.26 1 1.2 1.27 V(5)
Reference voltage See(11), –40°C ≤ TJ ≤ 125°C 1.19 1.27 V(4)
1.19 1.27 1.185 1.285 V(5)
Feedback pin bias current 20 40 20 40 20 40 nA(4)
–40°C ≤ TJ ≤ 125°C 60 nA (4)
60 60 nA(5)
Reference voltage temperature coefficient See(6) 20 20 50 ppm/°C
Feedback pin bias current temperature coefficient 0.1 0.1 0.1 nA/°C
ERROR COMPARATOR
Output leakage current VOH = 30 V 0.01 1 0.01 1 0.01 1 µA(4)
VOH = 30 V, –40°C ≤ TJ ≤ 125°C 2 µA(4)
2 2 µA(5)
Output low voltage VIN = (VONOM − 0.5 V), IOL = 400 µA 150 250 150 250 150 250 mV(4)
VIN = (VONOM − 0.5 V), IOL = 400 µA,
–40°C ≤ TJ ≤ 125°C
400 400 400 mV(4)
400 400 mV(5)
Upper threshold voltage See(12) 40 60 40 60 40 60 mV(4)
See(12), –40°C ≤ TJ ≤ 125°C 25 mV(4)
25 25 mV(5)
Lower threshold voltage See(12) 75 95 75 95 75 95 mV(4)
See(12), –40°C ≤ TJ ≤ 125°C 140 mV(4)
140 140 mV(5)
Hysteresis See(12) 15 15 15 mV
SHUTDOWN INPUT
Input 1.3 1.3 1.3 V
Logic voltage Low (Regulator ON), –40°C ≤ TJ ≤ 125°C 0.6 V(4)
0.7 0.7 V(5)
Logic voltage High (Regulator OFF), –40°C ≤ TJ ≤ 125°C 2 V(4)
2 2 V(5)
Shutdown pin input current Vshutdown = 2.4 V 30 50 30 50 30 50 µA(4)
Vshutdown = 2.4 V
–40°C ≤ TJ ≤ 125°C
100 µA(4)
100 100 µA(5)
Vshutdown = 30 V 450 600 450 600 450 600 µA(4)
Vshutdown = 30 V,
–40°C ≤ TJ ≤ 125°C
750 µA(4)
750 750 µA(5)
Regulator output current in shutdown See(13) 3 10 3 10 3 10 µA(4)
–40°C ≤ TJ ≤ 125°C 20 µA(4)
20 20 µA(5)
Unless otherwise noted, all limits apply for TA = TJ = 25°C as well as specified for VIN = (VONOM + 1 V), IL = 100 µA and CL = 1 µF for 5-V versions and 2.2 µF for 3-V and 3.3-V versions. Additional conditions for the 8-pin versions are FEEDBACK tied to VTAP, OUTPUT tied to SENSE, and VSHUTDOWN ≤ 0.8 V.
A Military RETS specification is available on request.
All LP2950 devices have the nominal output voltage coded as the last two digits of the part number. In the LP2951 products, the 3-V and 3.3-V versions are designated by the last two digits, but the 5-V version is denoted with no code at this location of the part number (refer to the Package Option Addendum at end of data sheet).
Ensured and 100% production tested.
Ensured but not 100% production tested. These limits are not used to calculate outgoing AQL levels.
Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation.
Line regulation for the LP2951-N is tested at 150°C for IL = 1 mA. For IL = 100 µA and TJ = 125°C, line regulation is specified by design to 0.2%. See Typical Characteristics for line regulation versus temperature and load current.
Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below its nominal value measured at 1-V differential. At very low values of programmed output voltage, the minimum input supply voltage of 2 V (2.3 V over temperature) must be taken into account.
Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN = 30 V (1.25-W pulse) for T = 10 ms.
VREF ≤ VOUT ≤ (VIN − 1 V), 2.3 V ≤ VIN ≤ 30 V, 100 µA ≤ IL ≤ 100 mA, TJ ≤ TJMAX.
Comparator thresholds are expressed in terms of a voltage differential at the FEEDBACK pin below the nominal reference voltage measured at VIN = (VO(NOM) + 1) V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = VOUT/VREF = (R1 + R2) / R2.For example, at a programmed output voltage of 5 V, the ERROR output is specified to go low when the output drops by 95 mV × 5 V / 1.235 V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% ensured.
VSHUTDOWN ≥ 2 V, VIN ≤ 30 V, VOUT = 0, FEEDBACK pin tied to VTAP.

Typical Characteristics

LP2950-N LP2951-N 854627.png Figure 1. Quiescent Current
LP2950-N LP2951-N 854629.png Figure 3. Input Current
LP2950-N LP2951-N 854631.png Figure 5. Output Voltage vs. Temperature of 3 Representative Units
LP2950-N LP2951-N 854633.png Figure 7. Quiescent Current
LP2950-N LP2951-N 854635.png Figure 9. Quiescent Current
LP2950-N LP2951-N 854637.png Figure 11. Dropout Voltage
LP2950-N LP2951-N 854639.png Figure 13. LP2951-N Minimum Operating Voltage
LP2950-N LP2951-N 854641.png Figure 15. LP2951-N Feedback Pin Current
LP2950-N LP2951-N 854643.png Figure 17. LP2951-N Comparator Sink Current
LP2950-N LP2951-N 854648.png Figure 19. Output Impedance
LP2950-N LP2951-N 854650.png Figure 21. Ripple Rejection
LP2950-N LP2951-N 854652.png Figure 23. LP2951-N Output Noise
LP2950-N LP2951-N 854654.png Figure 25. Shutdown Threshold Voltage
LP2950-N LP2951-N 854656.png Figure 27. LP2951-N Maximum Rated Output Current
LP2950-N LP2951-N 854658.png Figure 29. Thermal Response
LP2950-N LP2951-N 854672.gif Figure 31. LP2951-N Input Pin Current vs Input Voltage
LP2950-N LP2951-N 854628.png Figure 2. Dropout Characteristics
LP2950-N LP2951-N 854630.png Figure 4. Input Current
LP2950-N LP2951-N 854632.png Figure 6. Quiescent Current
LP2950-N LP2951-N 854634.png Figure 8. Quiescent Current
LP2950-N LP2951-N 854636.png Figure 10. Short Circuit Current
LP2950-N LP2951-N 854638.png Figure 12. Dropout Voltage
LP2950-N LP2951-N 854640.png Figure 14. LP2951-N Feedback Bias Current
LP2950-N LP2951-N 854642.png Figure 16. LP2951-N Error Comparator Output
LP2950-N LP2951-N 854647.png Figure 18. LP2951-N Enable Transient
LP2950-N LP2951-N 854649.png Figure 20. Ripple Rejection
LP2950-N LP2951-N 854651.png Figure 22. Ripple Rejection
LP2950-N LP2951-N 854653.png Figure 24. LP2951-N Divider Resistance
LP2950-N LP2951-N 854655.png Figure 26. Line Regulation
LP2950-N LP2951-N 854657.png Figure 28. LP2950-N Maximum Rated Output Current
LP2950-N LP2951-N 854663.png Figure 30. Output Capacitor ESR Range
LP2950-N LP2951-N 854673.gif Figure 32. LP2951-N Input Pin Current vs Input Voltage