SN74LVC1T45 Max Data Rates versus Switching Characteristics

Hello David, 

In the loosest terms - propogation delay is the time between when the signal changes on the input of the device and when that change is seen on the output of the device. Max data rate is the fastest signal that the device can handle. A device can have a very high propagation delay (delay between when the signal is seen on the input and passed to the output) but still be able to support a high data speed. 

A common misconception about logic devices is that the maximum data-signaling rate is equal to the inverse of the propagation delay. The maximum data rate on buffers is dependent on several factors, such as propagation delay matching, input sensitivity, and output edge rates. A device can have a high maximum signaling rate if the propagation delays from low-to-high and high-to-low are matched, the input is fast enough to respond to the fast data rate, and the output edge rate does not interfere with the low and high-level steady states.

From the example you give - 

I understand that the max data rates is 210 Mbps, which normally corresponds to a minimum bit duration of 4,76 ns. 

Now the switching characteristics give a maximum tplh to 5.8 ns and tphl to 5 ns. Both values normally define the tpd of the buffer. So how can I get a max data rate of 210 Mbps if the tpd is defined to max 5.8 ns?

The tpd of 5.8ns indicates that any change on the input will be seen at the output at a maximum of 5.8ns later. It should have no impact on the 4.76ns bit duration.

This device should be able to handle a 50Mbps signal.