SCEA135 june   2023 TXB0101 , TXB0102 , TXB0104 , TXB0104-Q1 , TXB0106 , TXB0106-Q1 , TXB0108 , TXB0302 , TXB0304 , TXS0101 , TXS0101-Q1 , TXS0102 , TXS0102-Q1 , TXS0104E , TXS0104E-Q1 , TXS0108E , TXS0108E-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2The One-shot's Designed Duration
    1. 2.1 Design Considerations
    2. 2.2 Recommended Parts
  6. 3Design Considerations for Slow Rise and Fall Times
    1. 3.1 Design Considerations
    2. 3.2 Recommended Parts
  7. 4Consider the Impact of External RC Components on Rise and Fall Times
    1. 4.1 Design Considerations
    2. 4.2 Recommended Parts
  8. 5Consider the Lumped Capacitance
    1. 5.1 Design Considerations
    2. 5.2 Recommended Parts
  9. 6Consider the Effects of Temperature on the Output Impedance
    1.     Design Considerations
  10. 7Summary
  11. 8References

Summary

  • Consider short enough traces for round-trip delay reflections within the one-shot duration of 10-30 ns.
  • Consider any tolerances of any additional RC components, similar to the data sheet recommendations.
  • Consider utilizing fast enough input edges per the input transition rate while avoiding floating inputs as stated in the data sheets.
  • Unless otherwise noted in the data sheets, makes sure <70 pF lumped capacitance designed for performance per the data sheet’s recommended data rates.
  • Avoid timing-out the one-shot duration with additional parasitic capacitance as trace length and connectors yields additional capacitive loading.
  • One-shot triggers when they detect rising or falling edges. Reflections and or ringing can cause false triggers. Ringing is also caused by capacitance and inductance of long cables and or traces and can also be amplified by unstable GND or VCC voltages.
  • Consider the impact on temperature per the output impedance, as mismatched impedance with PCB traces yield reflections that can be amplified by the one-shot as false edge triggers.