SNVS648J January   2010  – October 2015 LMZ14202

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
    6. 6.6 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 Constant On-Time Control (COT) Circuit Overview
      2. 7.3.2 Output Overvoltage Comparator
      3. 7.3.3 Current Limit
      4. 7.3.4 Thermal Protection
      5. 7.3.5 Zero Coil Current Detection
      6. 7.3.6 Prebiased Start-Up
    4. 7.4 Device Functional Modes
      1. 7.4.1 Discontinuous Conduction and Continuous Conduction Modes
  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 Design Steps for the LMZ14202 Application
          1. 8.2.2.1.1 Enable Divider, RENT and RENB Selection
          2. 8.2.2.1.2 Output Voltage Selection
          3. 8.2.2.1.3 Soft-Start Capacitor Selection
          4. 8.2.2.1.4 CO Selection
          5. 8.2.2.1.5 Input Capacitance (CIN) Selection
          6. 8.2.2.1.6 RDS(on) Resistor Selection
            1. 8.2.2.1.6.1 Discontinuous Conduction and Continuous Conduction Mode Selection
      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 and Board Thermal Requirements
    4. 10.4 Power Module SMT Guidelines
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 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)(2)
MIN MAX UNIT
VIN, RON to GND –0.3 43.5 V
EN, FB, SS to GND –0.3 7 V
TJ Junction temperature 150 °C
Peak reflow case temperature (30 s) 245 °C
Tstg Storage temperature –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) For soldering specifications, refer to the following document: www.ti.com/lit/snoa549c

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
VIN Input voltage 6 42 V
EN Enable voltage 0 6.5 V
TJ Junction temperature −40 125 °C

6.4 Thermal Information

THERMAL METRIC(1) LMZ14202 UNIT
NDW
(TO-PMOD)
7 PINS
RθJA Junction-to-ambient thermal resistance 4-layer JEDEC Printed circuit board, 100 vias, No air flow 19.3 °C/W
2-layer JEDEC Printed circuit board, No air flow 21.5 °C/W
RθJC(top) Junction-to-case (top) thermal resistance No air flow 1.9 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics

Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the junction temperature (TJ) range of –40°C to +125°C. Minimum and maximum limits are ensured through test, design or statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated the following conditions apply: VVIN = 24 V, VVOUT = 3.3 V
PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT
ENABLE CONTROL(3)
VEN EN threshold trip point VEN rising 1.18 V
–40°C ≤ TJ ≤ 125°C 1.1 1.25
VEN-HYS EN threshold hysteresis VEN falling 90 mV
SOFT-START
ISS SS source current VSS = 0 V 8 µA
–40°C ≤ TJ ≤ 125°C 5 11
ISS-DIS SS discharge current -200 µA
CURRENT LIMIT
ICL Current limit threshold d.c. average 2.6 A
–40°C ≤ TJ ≤ 125°C 2.3 3.65
ON/OFF TIMER
tON-MIN ON timer minimum pulse width 150 ns
tOFF OFF timer pulse width 260 ns
REGULATION AND OVERVOLTAGE COMPARATOR
VFB In-regulation feedback voltage VSS > 0.8 V, IO = 2 A 0.795 V
–40°C ≤ TJ ≤ 125°C 0.775 0.815
VSS >+ 0.8 V, IO = 10 mA 0.786 0.802 0.818 V
VFB-OV Feedback over-voltage protection threshold 0.92 V
IFB Feedback input bias current 5 nA
IQ Non-switching input current VFB = 0.86 V 1 mA
ISD Shutdown quiescent current VEN = 0 V 25 μA
THERMAL CHARACTERISTICS
TSD Thermal shutdown Rising 165 °C
TSD-HYST Thermal shutdown hysteresis Falling 15 °C
PERFORMANCE PARAMETERS
ΔVO Output voltage ripple 8 mVP-P
ΔVO/ΔVIN Line regulation 12 V ≤ VVIN ≤ 42 V, IO = 2 A 0.01%
ΔVO/IOUT Load regulation VVIN = 24 V 1.5 mV/A
η Efficiency VVIN = 24 V, VO = 3.3 V, IO = 1 A 86%
VVIN = 24 V, VO = 3.3 V, IO = 2 A 85%
(1) Minimum and maximum 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 Average Outgoing Quality Level (AOQL).
(2) Typical numbers are at 25°C and represent the most likely parametric norm.
(3) EN 55022:2006, +A1:2007, FCC Part 15 Subpart B: 2007. See AN-2024 LMZ1420x / LMZ1200x Evaluation Board (SNVA422) and layout for information on device under test.

6.6 Typical Characteristics

Unless otherwise specified, the following conditions apply: VVIN = 24 V; CIN = 10 µF, X7R ceramic; CO = 100 µF X7R ceramic; TA = 25°C.
LMZ14202 30114531.gif Figure 1. Efficiency 6-V Input
LMZ14202 30114503.gif Figure 3. Efficiency 12-V Input
LMZ14202 30114526.gif Figure 5. Efficiency 24-V Input
LMZ14202 30114529.gif Figure 7. Efficiency 36-V Input at 25°C
LMZ14202 30114550.gif Figure 9. Efficiency 42-V Input
LMZ14202 30114533.gif Figure 11. Efficiency 6-V Input, TA = 85°C
LMZ14202 30114540.gif Figure 13. Efficiency 8 V Input, TA = 85°C
LMZ14202 30114542.gif Figure 15. Efficiency 12-V Input, TA = 85°C
LMZ14202 30114544.gif Figure 17. Efficiency 24-V Input, TA = 85°C
LMZ14202 30114546.gif Figure 19. Efficiency 36-V Input, TA = 85°C
LMZ14202 30114552.gif Figure 21. Efficiency 42-V Input, TA = 85°C
LMZ14202 30114548.gif Figure 23. Line and Load Regulation
LMZ14202 30114505.gif Figure 25. Output Ripple
VIN = 24 V, VO = 3.3 V, 2 A, BW = 200 MHz
LMZ14202 30114570.gif Figure 27. Thermal Derating, VOUT = 3.3 V
LMZ14202 30114554.gif Figure 29. Current Limit, VOUT = 3.3 V,
LMZ14202 30114532.gif Figure 2. Dissipation 6-V Input
LMZ14202 30114504.gif Figure 4. Dissipation 12-V Input
LMZ14202 30114527.gif Figure 6. Dissipation 24-V Input
LMZ14202 30114530.gif Figure 8. Dissipation 36-V Input
LMZ14202 30114551.gif Figure 10. Dissipation 42-V Input
LMZ14202 30114534.gif Figure 12. Dissipation 6-V Input, TA = 85°C
LMZ14202 30114541.gif Figure 14. Dissipation 8-V Input, TA = 85°C
LMZ14202 30114543.gif Figure 16. Dissipation 12-V Input, TA = 85°C
LMZ14202 30114545.gif Figure 18. Dissipation 24-V Input, TA = 85°C
LMZ14202 30114547.gif Figure 20. Dissipation 36-V Input, TA = 85°C
LMZ14202 30114553.gif Figure 22. Dissipation 42-V Input, TA = 85°C
LMZ14202 30114569.gif Figure 24. Line and Load Regulation, TA = 85°C
LMZ14202 30114506.gif Figure 26. Transient Response
VIN = 24 V, VO = 3.3 V, 0.6-A to 2-A Step
LMZ14202 30114565.gif Figure 28. Current Limit, VOUT = 3.3 V
LMZ14202 30114568.gif Figure 30. Current Limit, VOUT = 3.3 V, TA = 85°C