TCA9555: PCA9555 and TCA9555

Len Hsu2

Part Number: TCA9555
Other Parts Discussed in Thread: PCA9555,

Hi team,

I have customer design in TCA9555 and PCA9555 at same design.

Here is their block.

And they found out if they turn the switch to low, point B will be 1.6V. And the issue only show at TCA9555 not PCA9555.

What's the different with TCA9555 and PCA9555? What makes this issue happen?

0 BOBBY over 2 years ago

Len,

There shouldn't be much different between the TCA9555 and the PCA9555.

How many units are they seeing this issue with?

Is there any observed damage to the device/functionality?

Has the customer performed an A-B-A test?

-Bobby

+1 Clemens Ladisch over 2 years ago

Guru 316920 points

The xCA9555 devices have internal 100 kΩ pull-up resistors. Those and R2 form a voltage divider.

What is the purpose of R2?

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