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CCS/CD4053B: question on control signal voltage level

Part Number: CD4053B

Tool/software: Code Composer Studio

if the power supply to CD4053 is VDD=5.5V VSS=0V VEE=-5.5V, can I use digital control signal at 3.3V (MCU IO) ?

Plus, is there a similar switch ic to CD4053 fitting to the above voltage setup, but with just two channels, I cannot find one. Just ask to make sure.

Thanks in advance

  • CD4053B,

    You cannot use digital control signal from your MCU I/O at 3.3 V to control CD4053B with VDD=5.5V VSS=0V VEE=-5.5V. 

    The Vih level scales with VDD-VEE as stated in the datasheet.  The datasheet states with VEE=VSS and VDD 10V the Vih is 7V.  When I tested in my lab Vih = ~ 5.9 V (there is some margin in the spec).

    When I tested the device with VDD=5.5V VSS=0V VEE=-5.5V, Vih = ~0.4 V and Vil = ~-5 V. 

    The CD4053B is a 3 channel 2:1 switch.  You can use the switch search tool on TI.com to filter on 2-channel 2:1 devices.  When I did the search I found 38 different 2-channel 2:1 switches but none of them were dual supply which is what I think you are looking for.  There should be some new devices coming in the future that are dual supply and 2-channel 2:1.

    Thank you,

    Adam

  • In reply to Adam Torma:

    Thanks Adam,
    But I don't fully understand yet. As you said, Vih is expected to be 7V above VEE, so 3.3V IO output should do. Or is it because the margin is too small for Vil=0V? Have you test it with Vih=3.3V and Vil=0V? does it work?
    I am still in design phase, haven't got any sample for CD4053B, so I am not sure if it works, as the spec is not very clear to me.
    Ning
  • In reply to WANG NING:

    Ning,

    If VDD=5.5V VSS=0V VEE=-5.5V, Vih ~0.4 V and Vil  ~ -4.5 V.  With the these power supply settings placing a 3.3 V signal on the CD4053B logic pin will set the switch logic high but 0V signal on the logic pin would not set it to logic low.  To set a logic low with those power supply conditions ~-4.5 V would need to be placed on the logic control pins.  

    The control logic Vih and Vil levels of the signal switch scale with the potential across the VDD and VEE.  Those logic input threasholds are also referenced to VEE.

    Let me know if this help more with your understanding.

    Adam

  • In reply to Adam Torma:

    Adam:

    In CD4053 datasheet, Vil should be Vss=0V?

  • In reply to WANG NING:

    Ning,

    I don't think that is what I was seeing in my lab set up. I will need to build the set up again to make sure I didn't make an error. What do you see on your testing?

    Adam
  • In reply to Adam Torma:

    As the datasheet is not clear, I did not pick this IC in case any risk. I use other switch.
  • In reply to WANG NING:

    Ning,

    Would you mind telling the e2e community which switch you picked instead so that they may find a switch has a more clear datasheet?

    Thank you,
    Adam

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