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CD40109B: CD40109B

Part Number: CD40109B
Other Parts Discussed in Thread: SN7400

I need to translate a driving voltage from 5 V to 15 V.

 

Your IC CD40109B is very interesting for this purpose. I am planning to supply VCC with 5 V and VDD with 15 V. I have following questions:

 

-          The IC seems very old. Is this part active (I mean for a long time)?

-          Do you have the same/similar IC inverting?

-          Do you have other suggestions?/Do you see problems in using the CD40109B for this purpose?

  • Hello Enzo,

    Regarding TI's obsolescence policy, we have an official answer in our FAQ located here, and we have a recent post on the subject that should help you out here.

    We do not have a device that is both an inverter and a level translator, however we do have CD4k (up to 18V) inverters and we have many 5V inverters, located here.

    Since I don't have many details on your application, I can't really give a well informed answer, but I'll be happy to give you my opinion.  Typically, when a 15V driver is required, it is for a fairly high power application (such as driving the gate of a power MOSFET).  In this case, I would recommend using a dedicated gate driver rather than a logic device since logic devices really can't source much current (note the rated current of just a few mA)

  • Dear Emrys,

    Thank you for your Answer! From the technical point of view this component fullfills all the requirement we need. (I implemented the circuit without inverting level shifter)

    I just need to know if we can use it concerning obsolescence. I checked your links but it was unclear for me.

    Can we buy the product for the next 10 years? (YES, NO, PROBABLY YES)

    If no it will be substitued by a pin compatible device?

    Thank you

    Enzo

  • Hi Enzo,

    I am not magic, and I have no way to foretell the future for you... if you ask me if I will be alive in 10 years (or even tomorrow), I cannot say for certain.

    I can, however, tell you TI's policy on obsolescence and give you my opinion.

    The policy basically boils down to this: TI will continue to sell a device as long as we have a customer buying it, unless something happens that forces us to no longer be able to produce said device.

    In my opinion, if you regularly order a part on an annual or quarterly basis from TI, then it will continue to be available for you. As an example, we are still shipping SN7400 units that were first designed in 1969 because we have customers who continue to buy them -- most manufacturers stopped making these a long time ago!

    Also, if something did come up that we would have to stop making a device, TI would notify you well in advance of that happening (I believe the policy says 1 year, but I could be wrong). We can't predict what will happen in the future, but we do everything we can to support our customers.