74HC123 5-10ms Pulse on Edge

[ripper121]

Hello:),
i have a Reed Contact which can be open or closed,on each change (Open to Close or Close to Open) Ineed a 5-10ms Pulse (HIGH-LOW-HIGH).

With 2uF and 10kOhm on CEXT and REXT i get about 6.75ms Pulse. (i used Page 10 Table 7 to calculate that).
On page 5 table 3 are the states.

http://www.nxp.com/documents/data_sheet/74HC_HCT123.pdf

Is my schematic and calculation correct?
Is it with this schematic possible?

[radar_macgyver]

Looks like you're in the ballpark.

http://www.ti.com/lit/an/scla014/scla014.pdf

Consider using a smaller C and larger R. The discharge current will be smaller, and hence the likelihood of that current causing ground bounce.

[ripper121]

Thank you for this info .
Can you say something about my schematic, will it work?
Because there are some undefined states (not in the table)