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SN74CBTLV3125: What is the minimum voltage of VIL

Part Number: SN74CBTLV3125

Hi,team,

I have one question about SN74CBTLV3125.

What is the minimum voltage of VIL? Does it mean if voltage is <0.8V, the output is ensured LOW?

Only maximum value is marked in datasheet.

Thanks.

Johnny

  • Johnny,

    The minimum voltage allowed on the OE pin is 0 V. 

    If the voltage on the control logic OE pin is <0.8V it will be recognized by the device as receiving a logic low signal.  The device will respond based on the truth table and turn on the A to B path. 

    The opposite is true for the Vih.  When the voltage on the OE pin is > 2 V the device will receive a logic high signal and respond based on the truth table turning off the A to B path making it Hi-Z.

    Thank you,

    Adam

  • In reply to Adam Torma:

    Adam,

    Thanks for reply.

    How about the risk if A port minimum voltage is -0.3V? Will it influence the logic output at B port?

    Thanks.

    Johnny

  • In reply to Adam Torma:

    Adam,
    What is the minimum voltage allowed on A and B path?

    I notice it rail-to-rail switching on Data I/O ports,so does it mean the Vi range allowed on A and B path is same as the Vcc which is -0.5~4.6V ?

    I got a signal which the minimum voltage is -0.4V through the path B,is there any risk on it?

    Thanks

  • In reply to Johnny Guo:

    Johnny,

    The SN74CBTLV3125 device doesn't have any drive capability it simply passes a voltage from one side of the switch to the other so the B port could be the input or output depending on where the source and the load is in the system.

    I understand the confusion when looking at the older datasheets that doesn't have a recommended operating conditions table but -0.3 V is outside the recommended operating conditions.  The recommended operating conditions for this device on the A and B signal path is 0 to Vcc.  

    There are ESD protection diodes on the A and B I/O path to Vcc and GND.  As the voltage on the I/O pins exceed 0 to Vcc the ESD diode will begin to conduct and cause leakage through the diode.    

    user5774538 does this help with your question as well?

    Thank you,

    Adam