8 I/O expander with PWM on a 400 kHz I²C bus
The Maxim Integrated MAX7315AUE+T is an 8-bit GPIO expander that connects to an I²C or SMBus master at up to 400 kHz. Each I/O is open-drain rated for 50 mA source/sink, enough to drive indicator LEDs directly without a transistor buffer. An integrated PWM generator on every output allows dimming or analog-style control — useful for panel backlights or status indicators where a separate PWM controller would add cost and board space. The interrupt output signals the host on input transitions, so the MCU doesn't have to poll the expander. That saves bus bandwidth and keeps the system in a low-power sleep state until a button press or sensor edge wakes it.
Housed in a 16-TSSOP (4.40 mm wide body), the MAX7315AUE+T fits on compact PCBs where a larger SOIC or SSOP would crowd adjacent traces. Cut Tape (CT) is also available for prototyping or low-volume builds.