SN74LV123A: pulse duration does not match calculation

Hi Hans,

Your calculations are correct - you would expect to get a 1us pulse from the real device. I see that you're using a simulation though. Have you read the simulation model notes?

I'm guessing that you're using the PSpice model available from our website. It includes these notes:

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* Notes: 
* 1. The MODEL IS INTENDED FOR 5V OPERATION AND REFLECTS THE PULSE DURATION 
*    AS SHOWN IN FIGURE 6 OF THE DATA SHEET.
* 2. THE MODEL MAY NOT MEET THE OTHER DEVICE PARAMETERS. 
* 3. THIS MODEL IS INTENDED FOR USE IN CADENCE V16.2 AND ABOVE WITH 
*    AUTOCONVERGE ENABLED. IF AUTOCONVERGE IS NOT USED, THE SIMULATION 
*    WILL LIKELY HAVE CONVERGENCE ERRORS.
* 4. THE VALUES OF R_EXT AND C_EXT IN THE SCHEMATIC MUST BE ENTERED AS 
*    PARAMETERS VIA THE PARAMS STATEMENT IN THE .SUBCKT LINE BELOW. 
*    IF THIS IS NOT DONE, THE MODEL WILL GIVE INCORRECT RESULTS.
* 
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