Hi all
I have question about GPIO specification.
I doubt that the DC/AC timing parameters are different.
Because the behavior is different in CMOS mode and Schmitt trigger mode in my board.
So I want to confirm the following.
1.
Does the DC parameter that is shown in P39 of IMX6SDLAEC is for CMOS mode ?
http://cache.freescale.com/files/32bit/doc/data_sheet/IMX6SDLAEC.pdf
2.
Are there any different DC and AC parameter in CMOS mode and schmitt trigger mode ?
3.
In my understanding, i.MX becomes slower to recognize a "high" level in schmitt trigger mode than CMOS mode.
Because of the delay, is there possibility that i.MX can't latch the data correctly ?
ko-hey
Hi ko-hey
1. yes
2. with schmitt input hysteresis enabled, trigger may be later than
without hysteresis, because additional time is needed for signal
to reach hysteresis level. For example without hysteresis enabled
typical trigger level 0.5*OVDD, with hysteresis enabled it will be
0.5*OVDD + hysteresis value. According to Footnote 3 :
Hysteresis of 250 mV is guaranteed over all operating conditions when hysteresis is enabled.
3. yes this is correct understanding.
>Because of the delay, is there possibility that i.MX can't latch the data correctly ?
no.
Best regards
igor
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Hi Igor
Let me confirm about question No.3.
You mean that i.MX may fail latching a data.
Is it correct ?
ko-hey
Hi ko-hey
no, meaning that i.MX will not fail latching a data.
Best regards
igor