SLVS052J April   1988  – September 2026 TL594

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 Switching Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 5V Reference Regulator
      2. 7.3.2 Undervoltage Lockout
      3. 7.3.3 Oscillator
      4. 7.3.4 Dead-Time Control
      5. 7.3.5 Comparator
      6. 7.3.6 Pulse-Width Modulation (PWM)
      7. 7.3.7 Error Amplifiers
      8. 7.3.8 Output-Control Input
      9. 7.3.9 Output Transistors
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Input Power Source
        2. 8.2.2.2 Control Circuits
          1. 8.2.2.2.1 Oscillator
          2. 8.2.2.2.2 Error Amplifier
          3. 8.2.2.2.3 Current-Limiting Amplifier
          4. 8.2.2.2.4 Soft Start
          5. 8.2.2.2.5 Setting the Dead Time
        3. 8.2.2.3 Inductor Calculations
        4. 8.2.2.4 Output Capacitance Calculations
        5. 8.2.2.5 Transistor Power-Switch Calculations
      3. 8.2.3 Application Curve
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Feedback Traces
        2. 8.4.1.2 Input or Output Capacitors
        3. 8.4.1.3 Compensation Components
        4. 8.4.1.4 Traces and Ground Planes
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.3.6 Pulse-Width Modulation (PWM)

The comparator also provides modulation control of the output pulse duration. For this, the ramp voltage across timing capacitor CT is compared to the control signal present at the output of the error amplifiers. The timing capacitor input incorporates a series diode that is omitted from the control signal input. This requires the control signal (error amplifier output) to be approximately 0.7V greater than the voltage across CT to inhibit the output logic, and specifies maximum duty cycle operation without requiring the control voltage to sink to a true ground potential. The output pulse duration varies from 97% of the period to 0 as the voltage present at the error amplifier output varies from 0.5V to 3.5V, respectively.