The special chip of -GPI0-KB module is PCA9555 of NXP company, which is a 40-bit general GPI0 expansion chip with 56-pin TSSOP package. The improved features include 4000pF drive capability, 5VI/0 port, working current less than 1mA, separate 1/0 port configuration, 400kHz I2C bus clock frequency and smaller packaging form. When the application needs additional I/0 ports to connect ACPI ("Advanced Configuration and Power Interface", a power management standard jointly developed by , and ) power switches, sensors, buttons, LEDs, fans, etc.it can use 1/0 expansion devices to achieve simple solutions. Colour:blue Material:PC Specification:PCA9555 Due to different product batches, the appearance , which does not affect the use Package Contents: 1 * Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.