SNVS447J January   2007  – November 2014 LM5576 , LM5576-Q1

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 Handling Ratings: LM5576
    3. 6.3 Handling Ratings: LM5576-Q1
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    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 Shutdown / Standby
      2. 7.3.2 Soft-Start
      3. 7.3.3 Thermal Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 High Voltage Start-Up Regulator
      2. 7.4.2 Oscillator and Sync Capability
      3. 7.4.3 Error Amplifier and PWM Comparator
      4. 7.4.4 Ramp Generator
      5. 7.4.5 Maximum Duty Cycle / Input Drop-Out Voltage
      6. 7.4.6 Boost Pin
      7. 7.4.7 Current Limit
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Bias Power Dissipation Reduction
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  External Components
        2. 8.2.2.2  R3 (RT)
        3. 8.2.2.3  L1
        4. 8.2.2.4  C3 (CRAMP)
        5. 8.2.2.5  C9, C10
        6. 8.2.2.6  D1
        7. 8.2.2.7  C1, C2
        8. 8.2.2.8  C8
        9. 8.2.2.9  C7
        10. 8.2.2.10 C4
        11. 8.2.2.11 R5, R6
        12. 8.2.2.12 R1, R2, C12
        13. 8.2.2.13 R7, C11
        14. 8.2.2.14 R4, C5, C6
      3. 8.2.3 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 Related Links
    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)(1)
MIN MAX UNIT
VIN to GND 76 V
BST to GND 90 V
PRE to GND 76 V
SW to GND (Steady State) –1.5 V
BST to VCC 76 V
SD, VCC to GND 14 V
BST to SW 14 V
OUT to GND Limited to VIN
SYNC, SS, FB, RAMP to GND 7 V
(1) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and specifications.

6.2 Handling Ratings: LM5576

MIN MAX UNIT
Tstg Storage temperature range –65 150 °C
V(ESD) Electrostatic discharge Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins(1) 2 kV
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.

6.3 Handling Ratings: LM5576-Q1

MIN MAX UNIT
Tstg Storage temperature range –65 150 °C
V(ESD) Electrostatic discharge Human body model (HBM), per AEC Q100-002(1) 2 kV
(1) AEC Q100-002 indicates HBM stressing is done in accordance with the ANSI/ESDA/JEDEC JS-001 specification.

6.4 Recommended Operating Conditions

MIN MAX UNIT
VIN 6 75 V
Operation Junction Temperature (Q0) −40 150 °C
Operation Junction Temperature (Q1) −40 125 °C

6.5 Thermal Information

THERMAL METRIC(1) LM5576 UNIT
PWP
20 PINS
RθJA Junction-to-ambient thermal resistance 40 °C/W
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.

6.6 Electrical Characteristics

Typical values correspond to TJ = 25°C, VIN = 48 V, RT = 32.4kΩ. Minimum and maximum limits apply over –40°C to 125°C junction temperature range unless otherwise stated.(2)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
STARTUP REGULATOR
VCC Reg VCC Regulator Output 6.85 7.15 7.45 V
VCC LDO Mode turn-off 9 V
VCC Current Limit VCC = 0 V 25 mA
VCC SUPPLY
VCC UVLO Threshold (VCC increasing) 5.03 5.35 5.67 V
VCC Undervoltage Hysteresis 0.25 V
Bias Current (Iin) FB = 1.3 V 3.4 4.5 mA
Shutdown Current (Iin) SD = 0 V 57 85 µA
SHUTDOWN THRESHOLDS
Shutdown Threshold (SD Increasing) 0.47 0.7 0.9 V
Shutdown Hysteresis 0.1 V
Standby Threshold (Standby Increasing) 1.17 1.225 1.28 V
Standby Hysteresis 0.1 V
SD Pull-up Current Source 5 µA
SWITCH CHARACTERISTICS
Buck Switch Rds(on) (Q0) 170 380 mΩ
Buck Switch Rds(on) (Q1) 170 340 mΩ
BOOST UVLO 3.8 V
BOOST UVLO Hysteresis 0.56 V
Pre-charge Switch Rds(on) 70 Ω
Pre-charge Switch on-time 265 ns
CURRENT LIMIT
Cycle by Cycle Current Limit (Q0) RAMP = 0 V 3.6 4.2 5.5 A
Cycle by Cycle Current Limit (Q1) RAMP = 0 V 3.6 4.2 5.1 A
Cycle by Cycle Current Limit Delay RAMP = 2.5 V 100 ns
SOFT-START
SS Current Source 7 10 14 µA
OSCILLATOR
Frequency1 180 200 220 kHz
Frequency2 RT = 11kΩ 425 485 545 kHz
SYNC Source Impedance 11 kΩ
SYNC Sink Impedance 110 Ω
SYNC Threshold (falling) 1.3 V
SYNC Frequency RT = 11kΩ 550 kHz
SYNC Pulse Width Minimum 15 ns
RAMP GENERATOR
Ramp Current 1 VIN = 60 V, VOUT=10 V 235 275 315 µA
Ramp Current 2 VIN = 10 V, VOUT=10 V 18 25 32 µA
PWM COMPARATOR
Forced Off-time (Q0) 390 500 590 ns
Forced Off-time (Q1) 416 500 575 ns
Min On-time 80 ns
COMP to PWM Comparator Offset 0.7 V
ERROR AMPLIFIER
Feedback Voltage (Q0) Vfb = COMP 1.207 1.225 1.243 V
Feedback Voltage (Q1) Vfb = COMP 1.207 1.225 1.243 V
FB Bias Current 17 nA
DC Gain 70 dB
COMP Sink / Source Current 3 mA
Unity Gain Bandwidth 3 MHz
DIODE SENSE RESISTANCE
DSENSE 42 mΩ
THERMAL SHUTDOWN
Tsd Thermal Shutdown Threshold (Q0) 180 °C
Tsd Thermal Shutdown Threshold (Q1) 165 °C
Thermal Shutdown Hysteresis 25 °C
(1) Absolute Maximum Ratings are limits beyond which damage to the device may occur. Recommended Operating Conditions are conditions under which operation of the device is intended to be functional. For ensured specifications and test conditions, see the Electrical Characteristics.
(2) Min and Max limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlation using Statistical Quality Control (SQC) methods. Limits are used to calculate Texas Instruments' Average Outgoing Quality Level (AOQL).

6.7 Typical Characteristics

LM5576 LM5576-Q1 20189920.gif Figure 1. Oscillator Frequency vs RT
LM5576 LM5576-Q1 20189921.gif Figure 3. Oscillator Frequency vs Temperature (Q1) FOSC = 200kHz
LM5576 LM5576-Q1 20189922.gif Figure 5. Soft Start Current vs Temperature (Q1)
LM5576 LM5576-Q1 20189924.gif Figure 7. VCC vs VIN RL = 7kω
LM5576 LM5576-Q1 20189926.gif Figure 9. Demoboard Efficiency vs IOUT and VIN
LM5576 LM5576-Q1 20189950.png Figure 2. Oscillator Frequency vs Temperature (Q0) FOSC = 200kHz
LM5576 LM5576-Q1 20189951.png
Figure 4. Soft Start Current vs Temperature (Q0)
LM5576 LM5576-Q1 20189923.gif Figure 6. VCC vs ICC VIN = 12 V
LM5576 LM5576-Q1 20189925.gif Figure 8. Error Amplifier Gain/Phase AVCL = 101