SLVSFG3 April   2020 TPS92612

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Typical Application Diagram
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Timing Requirements
    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 Device Bias
        1. 7.3.1.1 Power-On Reset (POR)
      2. 7.3.2 Constant-Current Driver
      3. 7.3.3 PWM Control
      4. 7.3.4 Protection
        1. 7.3.4.1 Short-to-GND Protection
        2. 7.3.4.2 Over Temperature Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Undervoltage Lockout, V(SUPPLY)< V(POR_rising)
      2. 7.4.2 Normal State, V(SUPPLY) ≥ 4.5 V
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Single LED Driver
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Single-Channel LED Driver With Heat Sharing
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.2 Constant-Current Driver

The TPS92612 device is a high-side constant-current driver. The device controls the output current through regulating the voltage drop on an external high-side current-sense resistor, R(SNS). An integrated error amplifier drives an internal power transistor to maintain the voltage drop on the current-sense resistor R(SNS) to V(CS_REG) and therefore regulates the current output to target value. When the output current is in regulation, the current value can be calculated by using Equation 1.

Equation 1. TPS92612 eq-1.gif

where

  • V(CS_REG) = 98 mV (typical)

When the SUPPLY-to-OUT voltage difference is below the required dropout voltage, V(DROPOUT), at a given output current, the TPS92612 is not able to deliver enough current output as set by the value of R(SNS), and the voltage across the current-sense resistor R(SNS) is less than V(CS_REG).