Question, input slow signal into GPIO of i.MX28

[Aemj]

Hi team,

I would like to ask about the input signal to GPIO of i.MX28.

According to i.MX28 datasheet(Table 25 Digital Pin DC Characteristics for GPIO in 3.3-V Mode), GPIO input ports have 0.8V-2V of threshold voltage.

In my customer’s board, some GPIO pins are used for input signals which have slow rise/fall time. For the input signals from external, it takes about 1mSec to cross the threshold range of 0.8-2V.

My customer worries whether such input to GPIO could affect to the reliability of i.MX28.

Are there any problems for that?

Thanks,

Miyamoto

[Yongxin]

Dear Miyamoto-san,

No, there is no problem for the 1ms threshold time form VIL to VIH. From Table 27 of the datasheet, the input buffer is hysteresis function.

Best Regards,

Yongxin

[Aemj]

Dear team,

Sorry for harrying you up but my customer is pushing me.

I would appreciate it as early as possible.

Thanks,

Miyamoto