1.

General description

SCL/SDA upstream pair fans out to four downstream pairs, or channels. Any individual

SCx/SDx channel or combination of channels can be selected, determined by the

contents of the programmable control register. Four interrupt inputs, INT0 to INT3, one for

each of the downstream pairs, are provided. One interrupt output, INT, acts as an AND of

the four interrupt inputs.

An active LOW reset input allows the PCA9545A to recover from a situation where one of

Power-on reset function.

the maximum high voltage which will be passed by the PCA9545A. This allows the use of

different bus voltages on each pair, so that 1.8 V or 2.5 V or 3.3 V parts can communicate

with 5 V parts without any additional protection. External pull-up resistors pull the bus up

to the desired voltage level for each channel. All I/O pins are 5 V tolerant.

2.

Features

JESD22-A115, and 1000 V CDM per JESD22-C101

PCA9545A

Rev. 03 — 3 March 2005

Product data sheet