over and under shoot of SN74AHC1G125

HIRATA MITSUO

Intellectual 490 points

Other Parts Discussed in Thread: SN74AHC1G125

SN74AHC1G125 has overshooting and undershooting over absolute voltage.

(see attached file : overshoot is 0.8V(>0.5V), undershoot is -1.08V(<-0.5V))

Now I check how to mearure,.

However if this wave form is correct, I would like to know whether this over/undershoot is problem or not?

Best regards,

Mitsuo Hirata

over 8 years ago

0 Britt Brooks - Online Design Tools over 8 years ago

TI__Mastermind 41310 points

Mitsuo-san,

I have moved your post into the product line forum.

0 ShreyasRao over 8 years ago in reply to Britt Brooks - Online Design Tools

TI__Guru 58310 points

Hi Mitsuo San ,

Abs max specification have the input and output abs max voltage which the pins can withstand , beyond which , there could be reliability concerns for the device . A small resistance on the input can help reduce the overshoots and undershoots to be below the abs max . It also helps in limiting the current into the device to be below the abs max spec .
The output waveforms overshoots and undershoots really do not depend on the input waveforms as such . The high drive can be limited also be output damping resistors , having proper bypass caps close to Vcc pin.

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over and under shoot of SN74AHC1G125