SNVS089O July   2000  – July 2015 LM3488

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 : LM3488
    3. 6.3 ESD Ratings: LM3488-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 Slope Compensation Ramp
      2. 7.3.2 Frequency Adjust/Synchronization/Shutdown
      3. 7.3.3 Short-Circuit Protection
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Boost Converter
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Custom Design with WEBENCH Tools
          2. 8.2.1.2.2 Power Inductor Selection
          3. 8.2.1.2.3 Programming the Output Voltage
          4. 8.2.1.2.4 Setting the Current Limit
          5. 8.2.1.2.5 Current Limit with External Slope Compensation
          6. 8.2.1.2.6 Power Diode Selection
          7. 8.2.1.2.7 Power MOSFET Selection
          8. 8.2.1.2.8 Input Capacitor Selection
          9. 8.2.1.2.9 Output Capacitor Selection
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Designing SEPIC Using LM3488
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Power MOSFET Selection
          2. 8.2.2.2.2 Power Diode Selection
          3. 8.2.2.2.3 Selection Of Inductors L1 and L2
          4. 8.2.2.2.4 Sense Resistor Selection
          5. 8.2.2.2.5 SEPIC Capacitor Selection
          6. 8.2.2.2.6 Input Capacitor Selection
          7. 8.2.2.2.7 Output Capacitor Selection
  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 Custom Design with WEBENCH Tools
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Related Links
    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

  • Automotive Grade Product, AEC-Q100 Qualified
  • 8-Lead VSSOP Package
  • Internal Push-Pull Driver With 1-A Peak Current Capability
  • Current Limit and Thermal Shutdown
  • Frequency Compensation Optimized With a Capacitor and a Resistor
  • Internal Soft-Start
  • Current Mode Operation
  • Undervoltage Lockout With Hysteresis
  • Key Specifications:
    • Wide Supply Voltage Range of 2.97 V to 40 V
    • 100-kHz to 1-MHz Adjustable and Synchronizable Clock Frequency
    • ±1.5% (Overtemperature) Internal Reference
    • 5-µA Shutdown Current (Overtemperature)
  • Create a Custom Design Using the LM3488 with the WEBENCH Power Designer

2 Applications

  • Automotive Start-Stop Applications
  • Automotive ADAS Driver Information
  • One Cell/Two Cell Li-ion Battery Powered Portable Bluetooth Audio Systems
  • Notebooks, PDAs, Digital Cameras, and other Portable Applications
  • Offline Power Supplies
  • Set-Top Boxes
  • Boost for Audio Amplifiers

3 Description

The LM3488 is a versatile low-side N-FET high-performance controller for switching regulators. This device is suitable for use in topologies requiring low-side FET, such as boost, flyback, or SEPIC. Moreover, the LM3488 can be operated at extremely high switching frequency to reduce the overall solution size. The switching frequency of LM3488 can be adjusted to any value from 100 kHz to 1 MHz by using a single external resistor or by synchronizing it to an external clock. Current mode control provides superior bandwidth and transient response, besides cycle-by-cycle current limiting. Output current can be programmed with a single external resistor.

The LM3488 has built-in features such as thermal shutdown, short-circuit protection, and overvoltage protection. Power-saving shutdown mode reduces the total supply current to 5 µA and allows power supply sequencing. Internal soft-start limits the inrush current at start-up.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM3488 VSSOP (8) 3.00 mm × 3.00 mm
LM3488-Q1
  1. For all available packages, see the orderable addendum at the end of the datasheet.

Typical SEPIC Converter

LM488 DC/DC Sepic Converter, Buck-Boost, Automotive 2.97V - 40V LM3488 LM3488-Q1 LM3488_SEPIC_schematic.png