• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 33 subscribers
  • Views 487 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.

DS100MB203: 3.3V could be applied to DS100MB203 SCL, SDA, SEL0 and SEL1 pin when VDD/VIN are off (0V)?

Kazuhiko Hirano
Genius 14978 points
Part Number: DS100MB203

Hello,

At my customer design, 3.3V could be applied to DS100MB203 SCL, SDA, SEL0 and SEL1 pin when VDD/VIN are off (0V).
They have a couple of questions as follows.

Q1:
SEL0 and SEL1 are LVCMOS input pins. Since Absolute Maximum Ratings of LVCMOS input / output voltage is -0.5V to +4V, applying 3.3V to SEL0 and SEL1 when VDD/VIN=0V is OK?

Q2:
How about SCL and SDA? They could be LVCMOS input or Open drain output when VDD is on. When VDD/VIN are off, 3.3V could be applied to SCL and SDA with no damage?

Best regards,

K.Hirano

  • 0
    TI__Mastermind 36103 points

    Hi K.Hirano,

    Kazuhiko Hirano said:
    Q1:
    SEL0 and SEL1 are LVCMOS input pins. Since Absolute Maximum Ratings of LVCMOS input / output voltage is -0.5V to +4V, applying 3.3V to SEL0 and SEL1 when VDD/VIN=0V is OK?

    Based on the absolute maximum ratings (below), applying 3.3V to LVCMOS pins without VDD/VIN should not cause permanent device damage.  However, please note footnote (1) below the absolute maximum ratings.  It is not recommended to regularly operate the device beyond the recommended operating conditions and doing so may impact device reliability.  For LVCMOS, the recommended operating condition is not specified, so I would recommend looking at the LVCMOS electrical parameters, which reference VIH-max as VDD.

    Kazuhiko Hirano said:
    Q2:
    How about SCL and SDA? They could be LVCMOS input or Open drain output when VDD is on. When VDD/VIN are off, 3.3V could be applied to SCL and SDA with no damage?

    Based on the recommended operating conditions, there is no VDD/VIN dependency on SCL/SDA, so it should be fine to apply 3.3V to these pins without device power.

    Thanks,

    Drew