SLVSEB3A June   2018  – January 2019 TLC6946 , TLC6948

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application Schematic of TLC6948 With 48-Multiplexing
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Switching Characteristics
    7. 7.7 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Pin Equivalent Input and Output Schematic Diagrams
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Built-In 16Kb Display Memory (SRAM)
      2. 9.3.2  GCLK Dual-Edge Operation
      3. 9.3.3  Programmable Constant-Sink Channel Current
        1. 9.3.3.1 Global Brightness Control (BC)
        2. 9.3.3.2 Select RIREF for a Given BC
      4. 9.3.4  Grayscale (GS) Function (PWM Control)
      5. 9.3.5  Serial Data Interface
      6. 9.3.6  LED-Open Detection (LOD)
      7. 9.3.7  Caterpillar Removal
      8. 9.3.8  Precharge FET
      9. 9.3.9  Thermal Shutdown
      10. 9.3.10 IREF Resistor Short Protection (ISP)
    4. 9.4 Device Functional Modes
      1. 9.4.1 Normal Operating Mode
      2. 9.4.2 Power-Save Mode (PSM)
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedures
        1. 10.2.2.1 Power Supply Voltage
        2. 10.2.2.2 Channel Current and Brightness Control
        3. 10.2.2.3 SCLK and GCLK Frequency
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Examples
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Related Links
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Community Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

9.3.3.1 Global Brightness Control (BC)

The TLC694x device is able to adjust the output current of all constant-current outputs simultaneously. This function is called global brightness control (BC). The global BC for all outputs is programmed with a 7-bit word, thus all output currents can be adjusted in 128 steps from 12.5% to 100.69% for a given current-programming resistor, RIREF (See Table 1). BC data can be set through the serial interface. When the BC data changes, the output current also changes immediately. When the device is powered on, the BC data in the function control register is set to 36h as the default value.

Table 1. Global BC Data vs Constant-Current Ratio and Set Current Value

BC DATA GAIN RATIO OF GAIN / GAIN_MAX (AT MAX BC) IOUT (mA) (IOLCmax= 25 mA, TYP) IOUT (mA) (IOLCmax= 2.4 mA, TYP)
BINARY DECIMAL HEX
000 0000 0 00 4 12.5% 3.13 0.3
000 0001 1 01 4.22 13.19% 3.3 0.32
000 0010 2 02 4.44 13.88% 3.47 0.33
... ... ... ... ... ... ...
011 0101 53 35 15.78 49.31% 12.33 1.18
011 0110 (Default) 54 (Default) 36 (Default) 16 50% 12.5 1.2
011 0111 55 37 16.22 50.69% 12.67 1.22
... ... ... ... ... ... ...
111 1101 125 7D 31.78 99.31% 24.83 2.38
111 1110 126 7E 32 100% 25 2.4
111 1111 127 7F 32.22 100.69% 25.17 2.42