SNVS136L September   1998  – June 2016 LM2672

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics - 3.3 V
    6. 7.6  Electrical Characteristics - 5 V
    7. 7.7  Electrical Characteristics - 12 V
    8. 7.8  Electrical Characteristics - Adjustable
    9. 7.9  Electrical Characteristics - All Output Voltage Versions
    10. 7.10 Typical Characteristics
    11. 7.11 Typical Characteristics - Fixed Output Voltage Versions
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Switch Output
      2. 9.3.2 C Boost
      3. 9.3.3 SYNC
      4. 9.3.4 Feedback
    4. 9.4 Device Functional Modes
      1. 9.4.1 ON/OFF
      2. 9.4.2 Shutdown Mode
      3. 9.4.3 Active Mode
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Typical Application for Fixed Output Voltage Versions
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Inductor Selection (L1)
          2. 10.2.1.2.2 Output Capacitor Selection (COUT)
          3. 10.2.1.2.3 Catch Diode Selection (D1)
          4. 10.2.1.2.4 Input Capacitor (CIN)
          5. 10.2.1.2.5 Boost Capacitor (CB)
          6. 10.2.1.2.6 Soft-Start Capacitor (CSS, Optional)
          7. 10.2.1.2.7 Frequency Synchronization (Optional)
        3. 10.2.1.3 Application Curves
      2. 10.2.2 Typical Application for Adjustable Output Voltage Versions
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedure
          1. 10.2.2.2.1 Programming Output Voltage
          2. 10.2.2.2.2 Inductor Selection (L1)
          3. 10.2.2.2.3 Output Capacitor SeIection (COUT)
          4. 10.2.2.2.4 Catch Diode Selection (D1)
          5. 10.2.2.2.5 Input Capacitor (CIN)
          6. 10.2.2.2.6 Boost Capacitor (CB)
        3. 10.2.2.3 Application Curve
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 WSON Package Devices
    2. 12.2 Layout Examples
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Community Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information
    1. 14.1 DAP (WSON Package)

Package Options

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

7 Specifications

7.1 Absolute Maximum Ratings

over recommended operating junction temperature range of –40°C to 125°C (unless otherwise noted)(1)
MIN MAX UNIT
Supply voltage 45 V
ON/OFF pin voltage, VSH –0.1 6 V
Switch voltage to ground –1 V
Boost pin voltage VSW + 8 V
Feedback pin voltage, VFB –0.3 14 V
Power dissipation Internally limited
Lead temperature D package Vapor phase (60s) 215 °C
Infrared (15s) 220
P package (soldering, 10s) 260
Maximum junction temperature, TJ 150 °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.

7.2 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.

7.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN MAX UNIT
Supply voltage 6.5 40 V
TJ Operating junction temperature –40 125 °C

7.4 Thermal Information

THERMAL METRIC(1)(2) LM2672 UNIT
D (SOIC) P (PDIP) WSON (NHN)
8 PINS 8 PINS 16 PINS
RθJA Junction-to-ambient thermal resistance 105 95 — °C/W
RθJC(top) Junction-to-case (top) thermal resistance — — — °C/W
RθJB Junction-to-board thermal resistance — — — °C/W
ψJT Junction-to-top characterization parameter — — — °C/W
ψJB Junction-to-board characterization parameter — — — °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance — — — °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.
(2) Thermal resistances were simulated on 4-layer JEDEC board.

7.5 Electrical Characteristics – 3.3 V

TJ = 25°C (unless otherwise noted; see Figure 19)(1)
PARAMETER TEST CONDITIONS MIN(2) TYP(3) MAX(2) UNIT
VOUT Output voltage VIN = 8 V to 40 V, ILOAD = 20 mA to 1 A TJ = 25°C 3.251 3.3 3.35 V
TJ = –40°C to 125°C 3.201 3.399
VIN = 6.5 V to 40 V,
ILOAD = 20 mA to 500 mA		 TJ = 25°C 3.35 3.3 3.35
TJ = –40°C to 125°C 3.201 3.399
η Efficiency VIN = 12 V, ILOAD = 1 A 86%
(1) External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator performance. When the LM2672 is used as shown in Figure 19 test circuits, system performance is as specified by the system parameters section of Electrical Characteristics.
(2) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested. All limits at temperature extremes are specified through correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
(3) Typical numbers are at 25°C and represent the most likely norm.

7.6 Electrical Characteristics – 5 V

TJ = 25°C (unless otherwise noted; see Figure 19)(1)
PARAMETER TEST CONDITIONS MIN(2) TYP(3) MAX(2) UNIT
VOUT Output voltage VIN = 8 V to 40 V, ILOAD = 20 mA to 1 A TJ = 25°C 4.925 5 5.075 V
TJ = –40°C to 125°C 4.85 5.15
VIN = 6.5 V to 40 V,
ILOAD = 20 mA to 500 mA		 TJ = 25°C 4.925 5 5.075
TJ = –40°C to 125°C 4.85 5.15
η Efficiency VIN = 12 V, ILOAD = 1 A 90%
(1) External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator performance. When the LM2672 is used as shown in Figure 19 test circuits, system performance is as specified by the system parameters section of Electrical Characteristics.
(2) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested. All limits at temperature extremes are specified through correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
(3) Typical numbers are at 25°C and represent the most likely norm.

7.7 Electrical Characteristics – 12 V

TJ = 25°C (unless otherwise noted; see Figure 19)(1)
PARAMETER TEST CONDITIONS MIN(2) TYP(3) MAX(2) UNIT
VOUT Output voltage VIN = 15 V to 40 V, ILOAD = 20 mA to 1 A TJ = 25°C 11.82 12 12.18 V
TJ = –40°C to 125°C 11.64 12.36
η Efficiency VIN = 24 V, ILOAD = 1 A 94%
(1) External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator performance. When the LM2672 is used as shown in Figure 19 test circuits, system performance is as specified by the system parameters section of Electrical Characteristics.
(2) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested. All limits at temperature extremes are specified through correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
(3) Typical numbers are at 25°C and represent the most likely norm.

7.8 Electrical Characteristics – Adjustable

TJ = 25°C (unless otherwise noted; see Figure 19)(1)
PARAMETER TEST CONDITIONS MIN(2) TYP(3) MAX(2) UNIT
VFB Feedback voltage VIN = 8 V to 40 V, ILOAD = 20 mA to 1 A, VOUT programmed for 5 V (see Figure 19) TJ = 25°C 1.192 1.21 1.228 V
TJ = –40°C to 125°C 1.174 1.246
VIN = 6.5 V to 40 V, ILOAD = 20 mA to 500 mA, VOUT programmed for 5 V (see Figure 19) TJ = 25°C 1.192 1.21 1.228
TJ = –40°C to 125°C 1.174 1.246
η Efficiency VIN = 12 V, ILOAD = 1 A 90%
(1) External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator performance. When the LM2672 is used as shown in Figure 19 test circuits, system performance is as specified by the system parameters section of Electrical Characteristics.
(2) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested. All limits at temperature extremes are specified through correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
(3) Typical numbers are at 25°C and represent the most likely norm.

7.9 Electrical Characteristics – All Output Voltage Versions

TJ = 25°C, VIN = 12 V for the 3.3 V, 5 V, and Adjustable versions and VIN = 24V for the 12V version, and ILOAD = 100 mA (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT
IQ Quiescent current VFEEDBACK = 8 V for 3.3 V, 5 V, and adjustable versions 2.5 3.6 mA
VFEEDBACK = 15 V for 12 V versions 2.5
ISTBY Standby quiescent current ON/OFF Pin = 0 V TJ = 25°C 50 100 μA
TJ = –40°C to 125°C 150
ICL Current limit 1.25 1.55 2.1 A
1.2 2.2
IL Output leakage current VSWITCH = 0 V, ON/OFF Pin = 0 V, VIN = 40 V 1 25 μA
VSWITCH = −1 V, ON/OFF Pin = 0 V 6 15 mA
RDS(ON) Switch on-resistance ISWITCH = 1 A TJ = 25°C 0.25 0.3 Ω
TJ = –40°C to 125°C 0.5
fO Oscillator frequency Measured at switch pin TJ = 25°C 260 kHz
TJ = –40°C to 125°C 225 275
D Maximum duty cycle TJ = 25°C 95%
Minimum duty cycle TJ = –40°C to 125°C 0%
IBIAS Feedback bias current VFEEDBACK = 1.3 V, adjustable version only 85 nA
VS/D ON/OFF pin voltage TJ = 25°C 1.4 V
TJ = –40°C to 125°C 0.8 2
IS/D ON/OFF pin current ON/OFF Pin = 0 V TJ = 25°C 20 μA
TJ = –40°C to 125°C 7 37
FSYNC Synchronization frequency VSYNC = 3.5 V, 50% duty cycle 400 kHz
VSYNC Synchronization threshold voltage 1.4 V
VSS Soft-start voltage TJ = 25°C 0.63 V
TJ = –40°C to 125°C 0.53 0.73
ISS Soft-start current TJ = 25°C 4.5 μA
TJ = –40°C to 125°C 1.5 6.9
(1) All limits specified at room temperature and at temperature extremes. All room temperature limits are 100% production tested. All limits at temperature extremes are specified through correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
(2) Typical numbers are at 25°C and represent the most likely norm.

7.10 Typical Characteristics

LM2672 1293403.png Figure 1. Normalized Output Voltage
LM2672 1293405.png Figure 3. Efficiency
LM2672 1293407.png Figure 5. Switch Current Limit
LM2672 1293409.png Figure 7. Standby Quiescent Current
LM2672 1293411.png Figure 9. ON/OFF Pin Current (Sourcing)
LM2672 1293413.png Figure 11. Feedback Pin Bias Current
LM2672 1293415.png Figure 13. Dropout Voltage, 3.3-V Option
LM2672 1293404.png Figure 2. Line Regulation
LM2672 1293406.png Figure 4. Drain-to-Source Resistance
LM2672 1293408.png Figure 6. Operating Quiescent Current
LM2672 1293410.png Figure 8. ON/OFF Threshold Voltage
LM2672 1293412.png Figure 10. Switching Frequency
LM2672 1293414.png Figure 12. Peak Switch Current
LM2672 1293416.png Figure 14. Dropout Voltage, 5-V Option

7.11 Typical Characteristics – Fixed Output Voltage Versions

see Figure 19
LM2672 1293418.png
VSW pin voltage, 10 V/div VIN = 20 V, VOUT = 5 V,
Inductor current, 0.5 A/div ILOAD = 1 A, L = 47 μH,
Output ripple voltage,
20 mV/div AC-coupled 		COUT = 68 μF,
COUTESR = 50 mΩ
Figure 15. Continuous Mode Switching Waveforms, Horizontal Time Base: 1 μs/div
LM2672 1293420.png
Output voltage, VIN = 20 V, VOUT = 5 V,
100 mV/div, AC-coupled ILOAD = 1 A, L = 47 μH,
Load current: 200 mA to
1 A load pulse		 COUT = 68 μF,
COUTESR = 50 mΩ
Figure 17. Load Transient Response for Continuous Mode, Horizontal Time Base: 50 μs/div
LM2672 1293419.png
VSW pin voltage, 10 V/div VIN = 20 V, VOUT = 5 V,
Inductor current, 0.5 A/div ILOAD = 300 mA, L = 15 μH,
Output ripple voltage,
20 mV/div AC-coupled		 COUT = 68 μF (2×),
COUTESR = 25 mΩ
Figure 16. Discontinuous Mode Switching Waveforms, Horizontal Time Base: 1 μs/div
LM2672 1293421.png
Output voltage, VIN = 20 V, VOUT = 5 V,
100 mV/div, AC-coupled L = 47 μH,
Load current: 100 mA to
300 mA load pulse		 COUT = 68 μF,
COUTESR = 50 mΩ
Figure 18. Load Transient Response for Discontinuous Mode, Horizontal Time Base: 200 μs/div