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CD4051B: CD4051B, CD4052B, CD4053B several questions

Part Number: CD4051B
Other Parts Discussed in Thread: CD4053B, CD4052B,

Hi all

Would you mind if we ask CD4051B, CD4052B and CD4053B?

<Question1>
RDS is 470ohm(typ) upto 1050ohm(max) in case of 25C.
So, if the device'S RDS is 1050ohm@25C, in case of 125C, RDS will be 2.5kohm?
Or, including above mention, in case of 125C, MAX RDS is 1.3kohm?

<Question2>
If this device has diode clump inside, do you have follows charactics?
-VF-IF charactics
-IR-VR charactics

<Question3>
About output capacitance, do you have Electrical Characteristics in case of 125C?

Kind regards

Hirotaka Matsumoto

  • Hi Matsumoto-san,

    Answer 1:

    The Ron will not go up to 2.5KOhms at 25C because the maximum boundary from datasheet says it is 1300Ohms. Please also be aware that this Ron is decreasing as the VDD goes higher. For example, when Vdd = 15V, the max Ron at 125C is only 300Ohms. 

    Answer 2:

    Internally, this device has ESD clamping diode. Would you let me know what VF-IF, IR-VR stands for? Also, it will be of great help if you can share what particular system level requirements you are investigating into

    Answer 3: 

    Exact capacitance is normally not critical and capacitance does not vary very much with temperature. Based on these two facts, industry common practice is only specifying capacitance at the typical test condition. 

  • Hi all

    We have additional questions as follow, could you give us the reply?

    <Question1>
    As our customer's recognition,
    in case of VDD=5V, Ron=1050ohm, OutputCOS=30pF and CL=50pF, Propagation Delay Time will be 84ns as our customer's calculation.
    So, why is there the difference between the datasheet and customer's calculation?
    Could you let us know the definition of "Propagation Delay Time(Signal input to output)"?

    <Question2>
    In relation to ESD clamping diode, do you have CAE(TINATI)'s equivalent model?
    If you don't have it, there is no matter.

    Kind regards,

    Hirotaka Matsumoto



  • Hello Matsumoto, 

    I do not know how your customer calculate. I built a circuit based on all the numbers you shared. The propagation delay from 50% of input voltage to 50% of output is about 58.668ns. Our datasheet shows the maximum propagation delay is 60ns. 

  • Hi Matsumoto,

    We do not have spice model for CD405x, but if you have any concern about ESD clamping. We can help you review your customer's schematic.
  • Fan san

    Thank you so much for your reply!

    Kind regards,

    Hirotaka Matsumoto