The LM8322 and LM8333 I/O companions allow engineers to repartition their designs by offloading tasks from the processor and adding features through a set of simple commands. The chips have embedded key-scan functions, I/O expansion, and PWM LED control capabilities.

The devices use a standard I2C-compatible bus and interrupt signal that require only three pins, and they operate over the industrial temperature range. The LM8322 supports keypad matrices up to 104 keys, the LM8333 up to 72. Both have 1.62 to 1.98-V single-supply operation. When there is no activity on the host bus or keypad, the devices automatically enter an 18-µW standby mode.