I²C Port Expanders with Eight I/O Ports

The MAX7328/MAX7329 are 2-wire serial-interfaced peripherals with eight I/O ports. Any port can be used as a logic input or an open-drain output.

All input ports are continuously monitored for state changes (transition detection). Transitions are alerted through the open-drain, 5.5V-tolerant active-low INT output.

The MAX7328 and MAX7329 versions differ only by their slave ID address ranges. The MAX7328 has a slave ID range of 0100xxx (0x20 to 0x27). The MAX7329 has a slave ID range of 0111xxx (0x38 to 0x3F).

For a similar part with overvoltage-protected I/Os and a bus active-low RST input that clears the I²C serial interface, refer to the MAX7321 data sheet. The MAX7328/MAX7329 are members of a family of pin-compatible port expanders with a choice of input ports, open-drain I/O ports, and push-pull output ports (see the Selector Guide in the full data sheet).

Applications

* Industrial * Notebooks * RAID * Servers

* 100kHz, 5.5V-Tolerant, I2C-Compatible Serial Interface

* 2.5V to 5.5V Operating Supply Voltage Range

* Low-Standby-Current Consumption of 10µA (max)

* I2C Bus-to-Parallel-Port Expander

* Open-Drain Interrupt Output Active-Low INT

* 8-Bit Remote I/O Port for the I2C Bus

* Latched Outputs with High-Current-Drive Capability for Directly Driving LEDs

* Address by Three Hardware Address Pins for Use of Up to Eight Devices (Up to 16 Using Both MAX7328/MAX7329)

* Second Sources to PCF8574 and PCF8574A