PCF8575CDWE4 (TEXAS INSTRUMENTS)

The PCF8575CDWE4 is a remote 16-bit I?C and SMBus I/O Expander with interrupt output designed for VCC operation. The PCF8575C provides general-purpose remote I/O expansion for most microcontroller families via the I?C interface serial clock (SCL) and serial data (SDA). The device features a 16-bit quasi-bidirectional input/output (I/O) port (P07-P00, P17-P10), including latched outputs with high-current drive capability for directly driving LEDs. Each quasi-bidirectional I/O can be used as an input or output without the use of a data-direction control signal. At power on, the I/Os are in 3-state mode. The strong pull up to VCC allows fast-rising edges into heavily loaded outputs. This device turns on when an output is written high and is switched off by the negative edge of SCL. The I/Os should be high before being used as inputs. After power on, as all the I/Os are set to 3-state, all of them can be used as inputs.