SLVSCQ4 October   2014 TLC5957

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Typical Application Circuit (Multiple Daisy Chained TLC5957s)
  5. 5 Revision History
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 Handling Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Pin Equivalent Input and Output Schematic Diagrams
    2. 8.2 Test Circuit
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Device Functional Modes
      1. 9.3.1  Brightness Control (BC) Function
      2. 9.3.2  Color Control (CC) Function
      3. 9.3.3  Select RIREF For a Given BC
      4. 9.3.4  Choosing BC/CC For a Different Application
        1. 9.3.4.1 Example 1: Red LED Current is 20mA, Green LED Needs 12mA, Blue LED needs 8mA
        2. 9.3.4.2 Example 2: Red LED Current is 5mA, Green LED Needs 2mA, Blue LED Needs 1mA.
      5. 9.3.5  LED Open Detection (LOD)
      6. 9.3.6  Poker Mode
      7. 9.3.7  Internal Circuit for Caterpillar Removal
      8. 9.3.8  Internal Pre-charge FET for Ghost Removal
      9. 9.3.9  Thermal Shutdown (TSD)
      10. 9.3.10 IREF Resistor Short Protection (ISP)
      11. 9.3.11 Noise Reduction
  10. 10Application and Implementation
    1. 10.1 Application Information
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Related Links
    2. 13.2 Trademarks
    3. 13.3 Electrostatic Discharge Caution
    4. 13.4 Glossary
  14. 14Mechanical, 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 Max BC/CC data
    • 1~20mA (VCC = 3.3V)
    • 1~25mA (VCC = 5V)
  • Global Brightness Control (BC): 3-Bit (8 Step)
  • Global Brightness Control (CC) for Each Color Group: 9-Bit (512 Step), Three Groups
  • LED Power Supply Voltage up to 10V
  • VCC = 3.0 to 5.5V
  • Knee Voltage Vout = 0.24V at 10mA
  • Constant Current Accuracy
    • Channel to Channel = ±1%(Typ), ±3%(Max)
    • Device to Device = ±1%(Typ), ±2%(Max)
  • Data Transfer Rate : 33MHz
  • Grayscale Control Clock : 33MHz
  • Pre-charge FET for Ghost Cancelling
  • Enhanced Circuit for Caterpillar Cancelling
  • Selectable Data Transfer Bit and PWM Bit (9 bit to 16 bit)
  • Selectable Traditional PWM and ES-PWM
  • LED Open Detection (LOD)
  • Thermal Shut Down (TSD)
  • Auto Display Repeat/Auto Data Refresh
  • Delay Switching to Prevent Inrush Current
  • Operating Temperature : –40°C to +85°C

2 Applications

  • LED Video Displays
  • LED Signboards

3 Description

The TLC5957 is a 48-channel constant current sink driver. Each channel has an individually-adjustable, 65536-step, pulse width modulation (PWM) grayscale (GS) brightness control.

The output channels are divided into three groups, each group has a 512 step color brightness control (CC), CC adjusts brightness between colors. The maximum current value of all 48 channels can be set by 8-step global brightness control (BC). BC adjusts brightness deviation between LED drivers. GS, CC and BC data are accessible via a serial interface port.

TLC5957 has one error flag: LED open detection (LOD), which can be read via a serial interface port. Each constant-current has a pre-charge field- effect transistor (FET), which can remove ghosting and improve display performance on the multiplexing LED display. Besides, TLC5957 has an enhanced circuit, it can cancel the caterpillar effect caused by LED open.

TLC5957 has a poker data transmission mode; GS data length can be configured from 9 bit to 16 bit according to PWM bits in each sub-segment. Poker Mode can significantly increase visual refresh rate in multiplexing applications.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
TLC5957 QFN (56) 8.0 mm × 8.0 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

4 Typical Application Circuit (Multiple Daisy Chained TLC5957s)

typapp_SLVSCQ4.gif