Multiplexing 2digit 7 segment display

[2MO]

Hi
I am working on a seven segment display, and i´ve got some problems:
-1) I tried to multiplexing two digits, but I don´t know if the time between clock and the data is two low, it is possible to see the flicker effect on the segments (sure that is it!!!), but if the time is increased, it is impossible to see the incremental of the least significative segment. Can somebody help me ?

Thanks

 

[AdamLink]

Are you using inter-digit blanking. There should be a small delay between displays enables (about 10us). This allows the eye to stop seeing the one digit before the other is lit(ghosting). This is known as persistence of vision. Look at the data sheet for any display driver (such as the ICM7217 or ICM7218). It will describe the process.