SX1509 GPIO Expanders

These devices can also act as level shifters to connect microcontrollers running at one voltage level to components running at a different voltage levels, thus eliminating the need for extra level translating circuits. The core is operating as low as 1.425 V while the dual I/O banks can operate between 1.2 V and 3.6 V independent of the core voltage and each other (5.5 V tolerant).

Semtechs' SX1509 feature fully programmable LED drivers with internal oscillators for enhanced lighting control such as intensity (via 256- step PWM), blinking and breathing (fade in/out), making them highly versatile for a wide range of LED applications.

In addition, keypad applications are also supported with the on-chip scanning engine which enables continuous keypad monitoring up to 64 keys without any additional host interaction and further reduce the bus activity.

The SX1509 have the ability to generate mask-programmable interrupts based on falling/rising edge of any of its GPIO lines. A dedicated pin indicates to a host controller that a state change occurred in one or more of the lines. Each GPIO is programmable via 8-bit configuration registers such as data registers, direction registers, pull-up/pull-down registers, interrupt mask registers, and interrupt registers. These I/O expanders come in small footprint packages and are rated from -40°C to +85°C temperature range.