SNVS334F January   2005  – January 2016 LM2734Z , LM2734Z-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 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 Theory of Operation
      2. 7.3.2 Boost Function
      3. 7.3.3 Soft-Start
      4. 7.3.4 Output Overvoltage Protection
      5. 7.3.5 Undervoltage Lockout
      6. 7.3.6 Current Limit
    4. 7.4 Device Functional Modes
      1. 7.4.1 Enable Pin and Shutdown Mode
      2. 7.4.2 Thermal Shutdown
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 LM2734Z Design Example 1
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Inductor Selection
          2. 8.2.1.2.2  Input Capacitor
          3. 8.2.1.2.3  Output Capacitor
          4. 8.2.1.2.4  Catch Diode
          5. 8.2.1.2.5  Boost Diode
          6. 8.2.1.2.6  Boost Capacitor
          7. 8.2.1.2.7  Output Voltage
          8. 8.2.1.2.8  Calculating Efficiency, and Junction Temperature
          9. 8.2.1.2.9  Calculating the LM2734Z Junction Temperature
          10. 8.2.1.2.10 WSON Package
          11. 8.2.1.2.11 Package Selection
        3. 8.2.1.3 Application Curve
      2. 8.2.2 LM2734Z Design Example 2
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
      3. 8.2.3 LM2734Z Design Example 3
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
      4. 8.2.4 LM2734Z Design Example 4
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Detailed Design Procedure
      5. 8.2.5 LM2734Z Design Example 5
        1. 8.2.5.1 Design Requirements
        2. 8.2.5.2 Detailed Design Procedure
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    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

1 Features

  • Qualified for Automotive Applications
  • AEC-Q100 Qualified With the Following Results:
    • Device Temperature Grade 1: –40°C to 125°C Ambient Operating Temperature Range
    • Device HBM ESD Classification Level 2
    • Device CDM ESD Classification Level C6
  • 6-pin SOT Package, or 6-Pin WSON Package
  • 3.0-V to 20-V Input Voltage Range
  • 0.8-V to 18-V Output Voltage Range
  • 1-A Output Current
  • 3-MHz Switching Frequency
  • 300-mΩ NMOS Switch
  • 30-nA Shutdown Current
  • 0.8-V, 2% Internal Voltage Reference
  • Internal Soft-Start
  • Current-Mode, PWM Operation
  • Thermal Shutdown

2 Applications

  • DSL Modems
  • Local Point of Load Regulation
  • Battery-Powered Devices
  • USB-Powered Devices
  • Automotive

3 Description

The LM2734Z regulator is a monolithic, high-frequency, PWM step-down DC–DC converter assembled in a thick 6-pin SOT and a WSON non-pullback package. The device provides all the active functions to provide local DC–DC conversion with fast transient response and accurate regulation in the smallest possible PCB area.

With a minimum of external components and online design support through WEBENCH™, the LM2734Z is easy to use. The ability to drive 1-A loads with an internal 300-mΩ NMOS switch using state-of-the-art 0.5-µm BiCMOS technology results in the best power density available. The world class control circuitry allows for ON-times as low as 13 ns, thus supporting exceptionally high-frequency conversion over the entire 3-V to 20-V input operating range down to the minimum output voltage of 0.8 V. Switching frequency is internally set to 3 MHz, allowing the use of extremely small surface mount inductors and chip capacitors. Even though the operating frequency is very high, efficiencies up to 85% are easy to achieve. External shutdown is included, featuring an ultra-low standby current of 30 nA. The LM2734Z uses current-mode control and internal compensation to provide high-performance regulation over a wide range of operating conditions. Additional features include internal soft-start circuitry to reduce inrush current, pulse-by-pulse current limit, thermal shutdown, and output overvoltage protection.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM2734Z WSON (6) 3.00 mm × 3.00 mm
SOT (6) 1.60 mm × 2.90 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Circuit

LM2734Z LM2734Z-Q1 20130301.gif

Efficiency vs Load Current

LM2734Z LM2734Z-Q1 20130345.png