SLFS083A July   2024  – October 2024 TLC3555-Q1

PRODMIX  

  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 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Monostable Operation
      2. 6.3.2 Astable Operation
      3. 6.3.3 Power-on Reset
      4. 6.3.4 Thermal Shutdown
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Missing-Pulse Detector
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
        3. 7.2.1.3 Application Curve
      2. 7.2.2 Pulse-Width Modulation
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
        3. 7.2.2.3 Application Curve
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
      1. 8.1.1 Related Documentation
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|8
  • DDF|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6.3.1 Monostable Operation

For monostable operation, connect the TLC3555-Q1 as in Figure 6-1. If the output is low, application of a negative-going pulse to the trigger (TRIG) sets the internal flip-flop, drives the output high, and turns off DISCH. Capacitor CT charges through RA until the voltage across the capacitor reaches the threshold voltage of the threshold (THRES) input. If TRIG returns to a high level, the output of the threshold comparator resets the flip-flop, drives the output low, and discharges CT through DISCH.

TLC3555-Q1 Circuit for Monostable Operation Figure 6-1 Circuit for Monostable Operation

Monostable operation initiates when the TRIG voltage is less than the trigger threshold. After initialization, the sequence ends only if TRIG is high for at least 500ns before the end of the timing interval. When the trigger is grounded, the comparator storage time can be as long as 500ns, which limits the minimum monostable pulse width to 500ns. As a result of the threshold level and saturation voltage of the discharge transistor, the output pulse duration is approximately tw = 1.1 × RA × CT. Figure 6-3 is a plot of the nominal pulse width for various values of RA and CT. The threshold levels and charge rates are directly proportional to the supply voltage (VDD). As a result, the timing interval is independent of the supply voltage if the supply voltage is constant during the time interval.

Apply a negative-going trigger pulse simultaneously to RESET and TRIG during the timing interval to discharge CT and reinitiate the cycle, commencing on the positive edge of the reset pulse. The output is held low for as long as the reset pulse is low.

TLC3555-Q1 Typical Monostable Waveforms
RA = 9.1kΩ CT = 0.01µF
Figure 6-2 Typical Monostable Waveforms
TLC3555-Q1 Simulated Output Pulse Width vs Capacitance
 
Figure 6-3 Simulated Output Pulse Width vs Capacitance