SBVS237 March   2014 TLC5955

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Terminal Configurations and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Handling Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Terminal-Equivalent Input and Output Schematic Diagrams
    2. 7.2 Test Circuits
    3. 7.3 Timing Diagrams
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Output Current Calculation
      2. 8.3.2 Register and Data Latch Configuration
        1. 8.3.2.1 769-Bit Common Shift Register
        2. 8.3.2.2 Grayscale (GS) Data Latch
        3. 8.3.2.3 Control Data Latch
        4. 8.3.2.4 Dot Correction (DC) Data Latch
        5. 8.3.2.5 Maximum Current (MC) Data Latch
        6. 8.3.2.6 Global Brightness Control (BC) Data Latch
        7. 8.3.2.7 Function Control (FC) Data Latch
      3. 8.3.3 Status Information Data (SID)
      4. 8.3.4 LED Open Detection (LOD)
      5. 8.3.5 LED Short Detection (LSD)
      6. 8.3.6 Noise Reduction
    4. 8.4 Device Functional Modes
      1. 8.4.1 Maximum Current Control (MC) Function
      2. 8.4.2 Dot Correction (DC) Function
      3. 8.4.3 Global Brightness Control (BC) Function
      4. 8.4.4 Grayscale (GS) Function (PWM Control)
        1. 8.4.4.1 Conventional PWM Control
        2. 8.4.4.2 Enhanced Spectrum (ES) PWM Control
        3. 8.4.4.3 Auto Display Repeat Function
        4. 8.4.4.4 Display Timing Reset Function
        5. 8.4.4.5 Auto Data Refresh Function
  9. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Daisy-Chain Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Step-by-Step Design Procedure
          2. 9.2.1.2.2 Maximum Current (MC) Data
          3. 9.2.1.2.3 Global Brightness Control (BC) Data
          4. 9.2.1.2.4 Dot Correction (DC) Data
          5. 9.2.1.2.5 Grayscale (GS) Data
          6. 9.2.1.2.6 Other Control Data
        3. 9.2.1.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • 48 Constant-Current Sink Output Channels
  • Sink Current Capability with Maximum MC, DC, and BC Data:
    • 23.9 mA (VCC ≤ 3.6 V, MC = 5)
    • 31.9 mA (VCC > 3.6 V, MC = 7)
  • Grayscale (GS) Control:
    • 16-Bit (65,536 Steps) with Enhanced Spectrum or Conventional PWM
  • Maximum Current (MC) Control:
    • 3 Bits (8 Steps) with a 3-mA to 30-mA Range
    • 3 MC Sets for Each Color Group
  • Dot Correction (DC) Control:
    • 7 Bits (128 Steps) with a 26.2% to 100% Range
  • Global Brightness Control (BC):
    • 7 Bits (128 Steps) with a 10% to 100% Range
    • 3 BC Sets for Each Color Group
  • LED Power-Supply Voltage: Up to 10 V
  • VCC: 3.0 V to 5.5 V
  • Constant-Current Accuracy:
    • Channel-to-Channel: ±2% (typ), ±5% (max)
    • Device-to-Device: ±2% (typ), ±4% (max)
  • Data Transfer Rate: 25 MHz
  • Grayscale Control Clock: 33 MHz
  • Auto Display Repeat
  • Display Timing Reset
  • Auto Data Refresh (GS and DC Only)
  • LED Open Detection (LOD)
  • LED Short Detection (LSD)
  • UVLO Sets Default Data
  • Delay Switching to Prevent Inrush Current
  • Operating Temperature: –40°C to +85°C

2 Applications

  • LED Video Displays
  • Variable Message Signs (VMS)
  • Illumination

3 Description

The TLC5955 is a 48-channel, constant-current sink driver. Each channel has an individually-adjustable, pulse width modulation (PWM), grayscale (GS) brightness control with 65,536 steps and 128 steps of constant-current dot correction (DC). DC adjusts brightness deviation between channels. All channels have a 128-step global brightness control (BC). BC adjusts brightness deviation between the R, G, B color group. The eight-step maximum current control (MC) selects the maximum output current range for all channels of each color group. GS, DC, BC, and MC data are accessible with a serial interface port.

The TLC5955 has two error flags: LED open detection (LOD) and LED short detection (LSD). The error detection results can be read with a serial interface port.

Device Information

ORDER NUMBER PACKAGE BODY SIZE
TLC5955DCA HTSSOP (56) 14,0 mm × 6,1 mm
TLC5955RTQ QFN (56) 8,0 mm × 8,0 mm

Application Circuit

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