SNOSB43C September   2011  – November 2016 LM3560

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 I2C Timing Specifications (SCL, SDA)
    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 Power Amplifier Synchronization (Tx1)
        1. 7.3.1.1 TX1 Shutdown
      2. 7.3.2 Independent LED Control
      3. 7.3.3 Hardware Torch
      4. 7.3.4 Fault Protections
        1. 7.3.4.1 Overvoltage Protection
        2. 7.3.4.2 Current Limit
        3. 7.3.4.3 Flash Timeout
        4. 7.3.4.4 Indicator LED/Thermistor (LED1/NTC)
          1. 7.3.4.4.1 Message Indicator Current Source (LEDI/NTC)
            1. 7.3.4.4.1.1 Message Indicator Example 1 (Single Pulse With Dead Time):
            2. 7.3.4.4.1.2 Message Indicator Example 2 (Multiple Pulses With Dead Time):
          2. 7.3.4.4.2 Updating The Message Indicator
      5. 7.3.5 Input Voltage Monitor
        1. 7.3.5.1 Input Voltage Flash Monitor (Flash Current Rising)
      6. 7.3.6 Last Flash Register
      7. 7.3.7 LED Voltage Monitor
      8. 7.3.8 ADC Delay
      9. 7.3.9 Flags Register and Fault Indicators
        1. 7.3.9.1 Flash Timeout
        2. 7.3.9.2 Thermal Shutdown
        3. 7.3.9.3 LED Fault
        4. 7.3.9.4 TX1 and TX2 Interrupt Flags
        5. 7.3.9.5 LED Thermal Fault (NTC Flag)
        6. 7.3.9.6 VIN Flash Monitor Fault
        7. 7.3.9.7 VIN Monitor Fault
    4. 7.4 Device Functional Modes
      1. 7.4.1  Start-Up (Enabling the Device)
      2. 7.4.2  Pass Mode
      3. 7.4.3  Flash Mode
      4. 7.4.4  Torch Mode
      5. 7.4.5  Privacy Indicator Mode
      6. 7.4.6  GPIO1 Mode
      7. 7.4.7  TX2/INT/GPIO2
      8. 7.4.8  TX2 Mode
        1. 7.4.8.1 TX2 Shutdown
      9. 7.4.9  GPIO2 Mode
      10. 7.4.10 Interrupt Output (INT Mode)
      11. 7.4.11 NTC Mode
      12. 7.4.12 Alternate External Torch (AET) Mode
      13. 7.4.13 Automatic Conversion Mode
      14. 7.4.14 Manual Conversion Mode
    5. 7.5 I2C-Compatible Interface
      1. 7.5.1 START and STOP Conditions
      2. 7.5.2 I2C-Compatible Chip Address
      3. 7.5.3 Transferring Data
    6. 7.6 Register Descriptions
      1. 7.6.1  Enable Register (Address 0x10)
      2. 7.6.2  Privacy Register (Address 0x11)
      3. 7.6.3  Indicator Register (Address 0x12)
      4. 7.6.4  Indicator Blinking Register (Address 0x13)
      5. 7.6.5  Privacy PWM Period Register (Address 0x14)
      6. 7.6.6  GPIO Register (Address 0x20)
      7. 7.6.7  LED Forward Voltage ADC (VLED Monitor Register, Address 0x30)
      8. 7.6.8  ADC Delay Register (Address 0x31)
      9. 7.6.9  VIN Monitor Register (Address 0x80)
      10. 7.6.10 Last Flash Register (Address 0x81)
      11. 7.6.11 Torch Brightness Register Descriptions (Address 0xA0)
      12. 7.6.12 Flash Brightness Register (Address 0xB0)
      13. 7.6.13 Flash Duration Register (Address 0xC0)
      14. 7.6.14 Flags Register (Address 0xD0)
      15. 7.6.15 Configuration Register 1 (Address 0xE0)
      16. 7.6.16 Configuration Register 2 (Address 0xF0)
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 LM3560 Typical Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Output Capacitor Selection
          2. 8.2.1.2.2 Input Capacitor Selection
          3. 8.2.1.2.3 Inductor Selection
      2. 8.2.2 NTC Thermistor Application
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Recommendations
    2. 10.2 Layout Example
  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 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • Dual High-Side Current Sources Allow for Grounded Cathode LED Operation
  • Accurate and Programmable LED Current from 31.25 mA to 2 A
  • Independent LED Current Source Programmability
  • Up to 90% Efficient
  • Ultra-Small Solution Size: < 26 mm2
  • Four Operating Modes: Torch, Flash, Privacy Indicate, and Message Indicator
  • 4-Bit ADC for VLED Monitoring
  • LED Thermal Sensing and Current Scale-Back
  • Hardware Flash and Torch Enable
  • Dual Synchronization Inputs for RF Power Amplifier Pulse Events
  • LED and Output Disconnect During Shutdown
  • Open and Short LED Detection
  • 400-kHz I2C-Compatible Interface
  • Active Low Hardware Reset
  • −40°C to +85°C Ambient Temperature Range

2 Applications

  • Camera Phone LED Flash
  • White LED Biasing

3 Description

The LM3560 is a 2-MHz fixed frequency synchronous boost converter with two 1000-mA constant current drivers for high-current white LEDs. The dual high-side current sources allow for grounded cathode LED operation and can be tied together for providing flash currents at up to 2 A through a single LED. An adaptive regulation method ensures the current for each LED remains in regulation and maximizes efficiency.

The LM3560 is controlled via an I2C-compatible interface. Features include an internal 4-bit ADC to monitor the LED voltage, independent LED current control, a hardware flash enable allowing a logic input to trigger the flash pulse, dual TX inputs which force the flash pulse into a low-current torch mode allowing for synchronization to RF power amplifier events or other high-current conditions, and an integrated comparator designed to monitor an NTC thermistor and provide an interrupt to the LED current. Additionally, an active high HWEN input provides a hardware shutdown during system software failures.

The device is available in an ultra-small 16-pin DSBGA package. The 2-MHz switching frequency, overvoltage protection and adjustable current limit allow for the use of tiny, low-profile (1-µH and 2.2-µH) inductors and ceramic (10-µF) capacitors.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM3560 DSBGA (16) 1.96 mm × 1.96 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application

LM3560 30102801.gif