Part Number: TXB0108
Hi,
As TXB0108 is auto bidirectional voltage translator, does it work like one IO is flowing A(input) to B(output) and another IO is flowing B(input) to A(output) at the same time ?
OR ALL the IOs have to be in same directional flow('B to A' OR 'A to B') at the same time ?
Thanks in advance.
bidirectional feature scope
Hello Vishnu,
The device operation is shown in the datasheet:
I know there's a lot going on, so I tried to simplify it a bit by highlighting two paths.
The yellow path is for normal (DC) operation. That inverter is always outputting on both sides of the device, but it has a series 4kohm resistor that limits the output current significantly.
The red path is the transient path that only activates when a level change is detected on the opposite side of the device. The two boxes labelled "One Shot" cause a very short pulse to trigger the inverters when the opposite input is switched from LOW to HIGH or HIGH to LOW.
It's important to note that the one-shot inverters do _not_ have series 4kohm resistors, and thus have much higher drive strength. This is what provides the TXB0108 with fast edges.
Here's a drawing (also from the datasheet) that shows a single IO cell:
I think it's a little clearer - here you can see that the one shots are actually built in two parts and either help the rising or the falling edge, depending on the detected change.
