SN74CB3Q6800 specifications of Cio(ON)

Takumi Suzuki1

Mastermind 8430 points

Other Parts Discussed in Thread: SN74CB3Q6800

Hi,

I'm looking for bus switch IC for a replacement which I use now.

It seems that SN74CB3Q6800DBQR seems to be the best alternative.

But I have one question about the product regarding its electrical characteristics, especially Cio(ON).

I looked into datasheets of others but none of them specifies Cio(ON).

As you know, those capacitance affect bus communication performance, especially its transaction speed.

I would like to know how I should take care of Cio(ON) when I design our bus interface circuit.

Also, I would very much appreciate it if you provide some information why only SN74CB3Q6800 has Cio(ON) specification.

Best Regards,

over 8 years ago

0 Adam Torma over 8 years ago

TI__Mastermind 45350 points

Takumi-san,

The Cio(ON) measurement is available for most of our signal switches as this is a important parasitic to characterize for a signal switch. You can also see it as Con or on-state capacitance in the electrical specifications table. You can see the test circuit below on how this measurement is taken. You are correct that this parasitic capacitance will effect slow down the rise times of signals through the switch.

As we are improving our signal switch parametric tables on Ti.com you can search and filter by on state capacitance parameter to find a switch that can meet your needs.

We would like to find the best switch for your needs.

What type of bus are you attempting to switch? How many lanes? What is the voltage and bandwidth of your signals? Do you need 1:1 switching or 1:2 switching?

Thank you,

Adam