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SN74AHC1G09: Bigger AND gate (more inputs) than SN74AHC1G09

Tim Zoley
Prodigy 60 points
Part Number: SN74AHC1G09
Other Parts Discussed in Thread: SN74AS808B, SN74AHC08, SN74HC21

Hello

Is there a bigger AND gate component with more inputs than SN74AHC1G09?

I'd like to AND together up to 16 signals, but in a signal package. Using SN74AHC1G09 in parallel is larger BOM area than I can afford.

Thanks

Tim

  • 0
    TI__Intellectual 2050 points
    HI Tim,

    Are you attemping to AND together 16 signals? Or looking for a package that has multiple AND gates in it to reduce the need for multiple single 2-input AND gates?

    We do not have a device that can do 16 signals, however we have the SN74AS808B that is a hex, dual input AND Gate Driver. With that you would have 6 AND gates in one package. 12 inputs and 6 outputs.

    Otherwise we have Quad 2-input AND gates such as the SN74AHC08. This gives you 4 AND gates. 8 inputs and 4 outputs.

    Also, the SN74HC21 is a dual 4-input AND gate. Two AND gates with 4 inputs. 8 inputs and 2 outputs.

    Regards,

    Joe
  • 0 in reply to Joe Stephan
    Prodigy 60 points
    Hi Joe,
    Yes, exactly I'm trying to AND several signals together into one output. The alternatives you've give could potentially work, however do you make versions with open-drain output instead of "high"?
  • 0
    TI__Guru* 96862 points

    Hi Tim,

    We have the SN74HC21 (and a few other '21 function devices in other families)  that are dual quad-input AND gates.  Using a 4 input AND gate reduces your required # of gates for AND'ing 16 signals from 15 to 5 and simplifies routing a bit, but it still requires 3 devices on the board.  The smallest package available for this device is the PW (TSSOP) package, which is 6.3 x 5.0mm, meaning the total required space is ~94.5 mm^2. (3 devices)

    With the SN74AS808B (hex 2-input AND gate), it is only available in larger packages (12.8 x 10.3mm), requiring ~395 mm^2. (3 devices)

    Using a more popular standard quad AND gate such as the SN74LVC08 gives the benefit of more package options -- a VQFN package is available at 3.5 x 3.5mm, requiring ~49 mm^2. (4 devices)

    From the standpoint of board area required, I would go with the SN74LVC08 in the VQFN package.  It will also do very well on power consumption.

  • 0 in reply to Emrys Maier
    TI__Guru* 96862 points

    I just realized that you were looking for open-drain parts -- I'm afraid we don't have a very large selection of open-drain AND gates.  You can convert a standard AND gate into an open-drain device by adding a diode and pull-up resistor to the output as shown here:

    This will eliminate the need for pull-ups at every AND gate output, and allow you to interface with your final device as though the last AND gate were open-drain.