16 Output I/O Expander Breakout - SX1509

From the shop's description

This is powerful 16 Output I/O Expander Breakout – based on chip SX1509 made by Semtech. What does it mean GPIO expander? It means that if you have only two pins signal (in your Arduino for example) you can use them as if they are 16 pin. The SX1509 module allows easy serial expansion of I/O through I2C interface. SX1509 also can be used a fully programmable LED Driver with excellent lighting control such as intensity, blinking and fading, make them suitable for a wide range of LED applications. SX1509 GPIO expander can also act as a level shifter to connect a microcontroller running at one voltage level to a component running at a different voltage level, thus eliminating the need for extra level translating circuits. In addition, keypad application is also supported with the on-chip scanning engine which enables continuous keypad monitoring up to 64 keys without any additional host interaction. Features 16 Channels of True Bi-directional Style I/O Integrated LED Driver with Intensity Control Enable Direct Level Shifting Between I/O Banks and Host Controller On-Chip Keypad Scanning Engine Supports Up to 8x8 Matrix (64 Keys) 5.5V Tolerant I/Os, Up to 15mA Output Sink on All I/Os Sparkfun guide and tutorial for SX1509 SXB1509 Datasheet.