DLPS240A June   2024  – August 2024 DLPA3085

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 SPI Timing Parameters
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Description
    3. 6.3 Feature Description
      1. 6.3.1 Supply and Monitoring
        1. 6.3.1.1 Supply
        2. 6.3.1.2 Monitoring
          1. 6.3.1.2.1 Block Faults
          2. 6.3.1.2.2 Auto LED Turn-Off Functionality
          3. 6.3.1.2.3 Thermal Protection
      2. 6.3.2 Illumination
        1. 6.3.2.1 Programmable Gain Block
        2. 6.3.2.2 LDO Illumination
        3. 6.3.2.3 Illumination Driver A
        4. 6.3.2.4 RGB Strobe Decoder
          1. 6.3.2.4.1 Break Before Make (BBM)
          2. 6.3.2.4.2 Openloop Voltage
          3. 6.3.2.4.3 Transient Current Limit
        5. 6.3.2.5 Illumination Monitoring
          1. 6.3.2.5.1 Power Good
          2. 6.3.2.5.2 Ratio Metric Overvoltage Protection
        6. 6.3.2.6 Illumination Driver Plus Power FETs Efficiency
      3. 6.3.3 External Power FET Selection
        1. 6.3.3.1 Threshold Voltage
        2. 6.3.3.2 Gate Charge and Gate Timing
        3. 6.3.3.3 RDS(ON)
      4. 6.3.4 DMD Supplies
        1. 6.3.4.1 LDO DMD
        2. 6.3.4.2 DMD HV Regulator
        3. 6.3.4.3 DMD/DLPC Buck Converters
        4. 6.3.4.4 DMD Monitoring
          1. 6.3.4.4.1 Power Good
          2. 6.3.4.4.2 Overvoltage Fault
      5. 6.3.5 Buck Converters
        1. 6.3.5.1 LDO Bucks
        2. 6.3.5.2 General Purpose Buck Converters
        3. 6.3.5.3 Buck Converter Monitoring
          1. 6.3.5.3.1 Power Good
          2. 6.3.5.3.2 Overvoltage Fault
        4. 6.3.5.4 Buck Converter Efficiency
      6. 6.3.6 Auxiliary LDOs
      7. 6.3.7 Measurement System
    4. 6.4 Device Functional Modes
    5. 6.5 Programming
      1. 6.5.1 SPI
      2. 6.5.2 Interrupt
      3. 6.5.3 Fast-Shutdown in Case of Fault
    6. 6.6 Register Maps
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Component Selection for General-Purpose Buck Converter
      3. 7.2.3 Application Curve
    3. 7.3 System Example With DLPA3085 Internal Block Diagram
  9. 8 Power Supply Recommendations
    1. 8.1 Power-Up and Power-Down Timing
  10. 9 Layout
    1. 9.1 Layout Guidelines
      1. 9.1.1 SPI Connections
      2. 9.1.2 RLIM Routing
      3. 9.1.3 LED Connection
    2. 9.2 Layout Example
    3. 9.3 Thermal Considerations
  11. 10Device and Documentation Support
    1. 10.1 Third-Party Products Disclaimer
    2. 10.2 Device Support
      1. 10.2.1 Device Nomenclature
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
6.3.2.4.3 Transient Current Limit

Typically, the forward voltages of the GREEN and BLUE diodes are close to each other (about 3V to 5V) however the forward voltage of the red diode is significantly lower (2V to 4V). This can lead to a current spike in the RED diode when the strobe controller switches from green or blue to red. This happens because VLED is initially at a higher voltage than required to drive the red diode. DLPA3085 provides transient current limiting for each switch to limit the current in the LEDs during the transition. The transient current limit value is controlled through register ILLUM_ILIM (0x02, bit [6:3]). In a typical application, it is required only for the RED diode. The value for ILLUM_ILIM (0x02, bit [6:3]) should be set at least 20% higher than the DC regulation current. Register ILLUM_SW_ILIM_EN (0x02, bit [2:0]) contains three bits to select which switch employs the transient current limiting feature. The effect of the transient current limit on the LED current is shown in Figure 6-8.

DLPA3085 LED Current Without (Left) and with (Right) Transient Current LimitFigure 6-8 LED Current Without (Left) and with (Right) Transient Current Limit