SNAS416K July   2007  – November 2019 LM48511

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      EMI Graph: LM48511 RF Emissions — 3-Inch Cable
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 VDD = 5 V
    6. 6.6 Electrical Characteristics VDD = 3.6 V
    7. 6.7 Electrical Characteristics VDD = 3 V
    8. 6.8 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 General Amplifier Function
      2. 7.3.2 Differential Amplifier Explanation
      3. 7.3.3 Audio Amplifier Power Dissipation and Efficiency
      4. 7.3.4 Regulator Power Dissipation
      5. 7.3.5 Shutdown Function
      6. 7.3.6 Regulator Feedback Select
    4. 7.4 Device Functional Modes
      1. 7.4.1 7.4.1 Fixed Frequency
      2. 7.4.2 7.4.2 Spread Spectrum Mode
  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  Proper Selection of External Components
        2. 8.2.2.2  Power Supply Bypassing
        3. 8.2.2.3  Audio Amplifier Gain Setting Resistor Selection
        4. 8.2.2.4  Audio Amplifier Input Capacitor Selection
        5. 8.2.2.5  Selecting Regulator Output Capacitor
        6. 8.2.2.6  Selecting Regulating Bypass Capacitor
        7. 8.2.2.7  Selecting the Soft-Start (CSS) Capacitor
        8. 8.2.2.8  Selecting Diode (D1)
        9. 8.2.2.9  Duty Cycle
        10. 8.2.2.10 Selecting Inductor Value
        11. 8.2.2.11 Inductor Supplies
        12. 8.2.2.12 Setting the Regulator Output Voltage (PV1)
        13. 8.2.2.13 Discontinuous and Continuous Operation
        14. 8.2.2.14 ISW Feed-Forward Compensation for Boost Converter
        15. 8.2.2.15 Calculating Regulator Output Current
        16. 8.2.2.16 Design Parameters VSW and ISW
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Power and Ground Circuits
      2. 10.1.2 Layout Helpful Hints
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

5 Pin Configuration and Functions

NHZ Package
24-Pin WQFN
Top View
LM48511 300222d4.gif

Pin Functions

PIN I/O DESCRIPTION
NAME NO.
DAP – — To be soldered to board for enhanced thermal dissipation. Connect to GND plane.
FB 19 — Regulator feedback input
Connect FB to an external resistive voltage divider to set the boost output voltage.
FB_GND0 21 — Ground return for R3, R1 resistor divider
FB_GND1 20 — Ground return for R3, R2 resistor divider
FB_SEL 1 I Regulator feedback select
Connect to VDD to select feedback network connected to FB_GND1. Connect to GND to select feedback network connected to FB_GND0.
GND 7 — Signal ground
IN– 15 I Amplifier inverting input
IN+ 16 I Amplifier noninverting input
LS+ 8 O Amplifier noninverting output
LS– 12 O Amplifier inverting output
LSGND 9, 11 — Amplifier H-Bridge ground
PV1 10 — Amplifier H-Bridge power supply
Connect to V1.
REGGND 22, 23 — Power ground (booster)
SD_AMP 5 I Amplifier active-low shutdown
Connect to VDD for normal operation. Connect to GND to disable amplifier.
SD_BOOST 24 I Regulator active-low shutdown.
Connect to VDD for normal operation. Connect to GND to disable regulator.
SOFT-START 4 — Soft-start capacitor
SS/FF 6 I Modulation mode select.
Connect to VDD for spread spectrum mode (SS). Connect to GND for fixed frequency mode (FF).
SW 2, 3 — Drain of the internal FET switch
V1 13 — Amplifier supply voltage
Connect to PV1
VDD 18 — Power supply
VG0+ 14 O Amplifier noninverting gain output
VG0– 17 O Amplifier inverting gain output