TLC5928: TLC5928 Cascade buffer

Hi,

I need to cascade 90 TLC5928 !

I have designed a board with 9 TLC5928s in cascade and I need to cascade 10 boards.
Each board is 20 cm long, the result is a 2m long line. It's a 190x8 pixels LED display.

I have added a CD4050 buffer to each board (output signal) for better signal quality.

When I send data to the line, the first board is OK, but the 2nd board as 1 bit lost and the 3rd as 2 bit lost, etc.

When I search in the datasheet, I have found that in page 7: SIN is read on rising CLK and SOUT change on rising clock too.

With oscilloscope I have observed that the CD4050 add a small delay on CLK, and that is suffisant to break the signal.

I have added a 1.5nf on the last SOUT that make the rising too slow and they are no bit lost with this "workaround".

Is exist a CD4050'equivalent with best speed ?

Regards,