• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 15 subscribers
  • Views 95 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

ISO7341FC: Propagation delay details

Joao Barbosa
Prodigy 20 points

Part Number: ISO7341FC
Other Parts Discussed in Thread: ISO6441

Hello,
In the ISO7341 datasheet, I see the following information related to switching characteristics:
  • Separate switching‑characteristics tables for 5 V and 3.3 V supplies
  • Propagation delay and rise/fall time specifications
  • Rise and fall times specified for a 15 pF load
  • Figure 11, which shows the variation of typical propagation delay versus temperature
Based on this, I have a few questions:
  1. Mixed‑supply operation:
    For the case where VCC1 = 3.3 V and VCC2 = 5 V, what would be the expected min / typ / max propagation delay?
    Is it a reasonable and recommended approach to use the worst‑case propagation delay between the 3.3 V and 5 V tables for timing analysis?
  2. Sources of propagation delay variation:
    Besides temperature, what are the main contributors to propagation delay variation in this device?
    Is there any characterization data or guidance on the influence of Vcc on the min / typ / max propagation delay values?
Thank you for your support.
Best regards,
João
  • 0
    TI__Prodigy 210 points

    Hey João, 

    Thanks for reaching out. For mixed 3.3V/5V operation, the propagation delay will be related more closely to the VCC on the output side (VCC2). 

    If VCC2 = 5V, prop delay time will be closer to the values found in the 5V Supply Table (Table 7.13).

    Further, ISO7341 is a legacy device from TI. For improved timing performance and reliability, please consider switching to our newest generation ISO6441 device. It will be a pin-to-pin drop in replacement for ISO7341. You can view more info on TI.com here.

    Let me know if you have any more questions.

    - Sara