TXS0108E: Max data rate

Hailiang Zhang

Part Number: TXS0108E
Other Parts Discussed in Thread: LSF0108

Hi Expert,

Can you help clarify why the device's maximum rate for Open drain applications is much lower than the rate for push pull applications?

Regards,
Hailiang

5 months ago

0 Jack Guan 5 months ago

TI__Guru 53341 points

Hi Hailiang,

Open drain signals are slower due to the lack of the PMOS drivers in its architecture (it depends only on external pull-ups for the rise time of the signal).

Regards,

Jack

0 Hailiang Zhang 5 months ago in reply to Jack Guan

TI__Genius 12710 points

Hi Jack,

The pull up will affect the data rate of open drain, right? So with a stronger pull up, the data rate will higher, why we define the max data rate as 1.2M?

Regards,
Hailiang

0 Joshua Salinas 5 months ago in reply to Hailiang Zhang

TI__Mastermind 35450 points

Hello Hailiang,

We will take a look at your question and respond by Monday. Thanks!

Regards,

Josh

+1 Jack Guan 5 months ago in reply to Joshua Salinas

TI__Guru 53341 points

Hi Hailiang,

You are correct, however it is not suggested to use external pullups with this device due to heightened VOL levels as a parallel network is formed with the internal 10kohm pullups.

If customer wants to achieve faster open-drain data rate, they can also refer to the LSF0108 here that requires external pullups (in which its max supported freq. is directly depended on the external RC load).

Regards,

Jack

Interface

Interface forum

TXS0108E: Max data rate