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CD4053B: Output Condition when device is not power supplied with any INH

Kedar Manishankar
Mastermind 24075 points
Part Number: CD4053B
Other Parts Discussed in Thread: SN74CBTLV3257

E2E,

Is CD4053B output condition in high impedance when the device is not power supplied with any INH pin position?

I looked for relevant documentation regarding this condition in the datasheet but could not find it.

Kedar Manishankar

  • 0
    TI__Mastermind 45430 points

    Kedar,

    You are correct there isn't any documentation specifying the status of the switch with the supply at 0V.  Why do you require this condition in your design?

    You can search for devices that are high impedance when Vcc= 0V by using the TI.com switch search tool for switches with powered off protection. 

    If the switch has this feature, you will find a spec in the datasheet for the leakage when Vcc = 0V which implies high impedance.

    Why do you need a switch to do in your design?   What are the requirements so we can help you find a device with that feature? 

    Thank you,

    Adam  

  • 0
    Prodigy 60 points
    Goodmorning, I am the utilizer. The reason of the question is that I cannot drive the INH pin of the device, but only cut-off the power supply, so I need to know if the other devices connected at the output can be affected when the device is not powered even with the INH pin to GND through a 1kOhm resistor. Waiting for your kind answer, I thank you. Best regards. Christian
  • 0 in reply to Christian Bacchetta
    TI__Mastermind 45430 points
    Christian,

    We cannot guarantee Hi-Z isolation when the power is not supplied to our switches unless it has the feature described above. If you desire a device that needs to have the signal path Hi-Z when Vcc = 0V we need to find a device with the leakage spec with Vcc = 0V to guarantee that behavior.

    Do you have any more information like a diagram or what type of switch you need? what voltage do you need to support on the signal path? How many signal paths to do you have? Do you want to have a 1:1, 2:1, 4:1, etc.

    We can help you select a different device.

    Thank you,
    Adam
  • 0 in reply to Adam Torma
    Prodigy 60 points

    Goodmorning Adam,

    the characteristics of layout that I need are related the the device I chosen.

    The most important datum is the temperature, which is min. -45°C operative. Have you got any proposal ? Can you get the information for this device, because I think that the device has a profile of test for its validation.

    Waiting for your kind answer, thank you.

    Regards.

    Christian

  • 0 in reply to Christian Bacchetta
    TI__Mastermind 45430 points

    Christian,

    The CD4053 is a 3-channel 2:1 multiplexer.  Unfortunately we do not have any 2:1 multiplexers that we guarantee Hi-Z when Vcc = 0V and operation at -45 deg C. 

     We have several 2:1 devices that we guarantee Hi-Z when Vcc =0V (powered off protection) I found using the TI.com switch search tool like the SN74CBTLV3257.  However they only guarantee the specified performance down to -40 deg C.   

    Thank you,

    Adam

  • 0 in reply to Adam Torma
    Prodigy 60 points

    Hi Adam,

    a question: is it possible to provide the dedicated test, by your side ?

    Thank you.

    Regards.

    Christian Bacchetta

  • 0 in reply to Christian Bacchetta
    TI__Mastermind 45430 points

    Christian,

    Unfortunately we cannot provide dedicated testing of Hi-Z when Vcc = 0 V for the CD4053B because we cannot garuntee the performance of this feature with this device.  I can only recommend using devices that have the powered off protection feature and the leakage currents specified in the datasheet when Vcc = 0 V.

    Thank you,

    Adam