The SX1510B, SX1511B and SX1512B are complete ultra low voltage General Purpose parallel Input/Output (GPIO) expanders ideal for low power handheld battery powered equipment. This family of GPIOs comes in 4-, 8-, 16-channel configuration and allows easy serial expansion of I/O through a standard SPI interface. GPIO devices can provide additional control and monitoring when the microcontroller or chipset has insufficient I/O ports, or in systems where serial communication and control from a remote location is advantageous.