GPIO扩展LED闪烁 NXP 2/4/8/16-bit I2C/SMBus LED blinkers PCA9550/51/52/53 LED blinking with GPIO expansion These I2C/SMBus-compatible GPIO expanders, optimized for blinking in LED-status applications, support two user-programmable blink rates, without overloading the I2C-bus or tying up the I2C- bus master. Key features Applications 4 Compatible with I2C-bus and SMBus 4 LED status 4 Two user-programmable blink rates and duty cycles ……