The PCA9557PWR is a remote 8-bit I²C and SMBus low-power I/O Expander with reset and configuration registers designed for VCC operation. The device provides general-purpose remote I/O expansion for most microcontroller families via the I²C interface (serial clock (SCL) and serial data (SDA)). The PCA9557 consists of one 8-bit configuration (input or output selection), input port, output port and polarity inversion (active-high) registers. At power on, the I/Os are configured as inputs. However, the system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding input or output register. The polarity of the input port register can be inverted with the polarity inversion register. All registers can be read by the system master.
● 1µA Maximum low standby-current consumption
● I²C to parallel port expander
● Three hardware address pins allow up to eight devices
● Lower-voltage higher-performance migration path
● Input/output configuration register
● Polarity inversion register
● Active-low reset input
● Internal power-on reset
● High-impedance open drain on P0
● Power up with all channels configured as inputs
● Green product and no Sb/Br
●This device has limited built-in ESD protection, leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
