2-Wire-Interfaced, 2.5V to 5.5V, 20-Port or 28-Port I/O Expander

The MAX7300 compact, serial-interfaced, I/O expansion peripheral provides microprocessors with up to 28 ports. Each port is individually user configurable to either a logic input or logic output.

Each port can be configured as either a push-pull logic output capable of sinking 10mA and sourcing 4.5mA, or a Schmitt logic input with optional internal pullup. Seven ports feature configurable transition detection logic, which generates an interrupt upon change of port logic level. The MAX7300 is controlled through an I²C-compatible 2-wire serial interface, and uses four-level logic to allow 16 I²C addresses from only two select pins.

The MAX7300AAX and MAX7300ATL have 28 ports and are available in 36-pin SSOP and 40-pin thin QFN packages, respectively. The MAX7300AAI and MAX7300ATI have 20 ports and are available in 28-pin SSOP and thin QFN packages. For an SPI™-interfaced version, refer to the MAX7301 data sheet. For a pin-compatible port expander with additional 24mA constant-current LED drive capability, refer to the MAX6956 data sheet.

Applications

* Industrial Controllers * System Monitoring * White Goods

* 400kbps I²C-Compatible Serial Interface

* 2.5V to 5.5V Operation

* -40°C to +125°C Temperature Range

* 20 or 28 I/O Ports, Each Configurable as

* Push-Pull Logic Output

* Schmitt Logic Input

* Schmitt Logic Input with Internal Pullup

* 11µA (max) Shutdown Current

* Logic Transition Detection for Seven I/O Ports