https://www.nxp.com.cn/part/PCA9555D
特点
16-bit I2C-bus/SMBus I/O Expander with Interrupt in SO24 package
数据手册:
PDF
https://www.nxp.com.cn/docs/en/data-sheet/PCA9555.pdf
所有信息 PCA9555
封装
SO24: plastic small outline package; 24 leads; body width 7.5 mm
更多信息 PCA9555
The PCA9555 is a 24-pin CMOS device that provides 16 bits of
General Purpose parallel Input/Output (GPIO) expansion for I²C-bus/SMBus
applications and was developed to enhance the NXP Semiconductors family
of I²C-bus I/O expanders. The improvements include higher drive
capability, 5 V I/O tolerance, lower supply current, individual I/O
configuration, and smaller packaging. I/O expanders provide a simple
solution when additional I/O is needed for ACPI power switches, sensors,
push buttons, LEDs, fans, etc.
The PCA9555 consists of two 8-bit Configuration (Input or Output
selection); Input, Output and Polarity Inversion (active HIGH or active
LOW operation) registers. The system controller 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 read register can be inverted with
the Polarity Inversion register. All registers can be read by the system
controller. Although pin-to-pin and I²C-bus address compatible with the
PCF8575, software changes are required due to the enhancements, and are
discussed in Application Note AN469.
The PCA9555 open-drain interrupt output is activated when any input
state differs from its corresponding input port register state and is
used to indicate to the system controller that an input state has
changed. The power-on reset sets the registers to their default values
and initializes the device state machine.
Three hardware pins (A0, A1, A2) vary the fixed I²C-bus address and
allow up to eight devices to share the same I²C-bus/SMBus. The fixed
I²C-bus address of the PCA9555 is the same as the PCA9554, allowing up
to eight of these devices in any combination to share the same
I²C-bus/SMBus.
