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Output current of SN74AHCT244PW

Hello,

 

We are trying to figure out if it would be acceptable to drive a MOSFET at a frequency of 20kHz using one of the output of a 74AHC244. We have captured the current waveforms during turn-on and turn-off of the FET, they are provided below.

 

While the RMS is well within the Io spec. of table7 of the datasheet (“Limiting values”), the instantaneous current goes over the limit. I was wondering if the Io spec. refers to continuous current draw only or if it represent max. instantaneous current as well.

 

Would the following patterns present a reliability issue for the device if repeated continuously at a frequency of 20kHz.

 

 

 

 

 

Thank you,

 

  • Hi Doug,
    There's no time limit on the absolute maximum ratings table for a reason. If one of those values is exceeded, we can no longer guarantee that the device will continue to function -- ie it could be broken on the very first time you exceed an absolute maximum rating.

    I would recommend using a device rated for the currents required. Perhaps a MOSFET gate driver?
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