The MAX7312 is a 2-wire-interfaced expander that provides 16-bit parallel input/output (I/O) port expansion in SMBus™ and I2C applications. The MAX7312 consists of input port registers, output port registers, polarity inversion registers, configuration registers, a bus timeout register, and an I2C-compatible serial interface logic, compatible with SMBus. The system master can invert the MAX7312 input data by writing to the active-high polarity inversion register. The system master can enable or disable bus timeout by writing to the bus timeout register. Any of the 16 I/O ports can be configured as an input or an output. A power-on reset (POR) initializes the 16 I/Os as inputs. Three address select pins configure the part to one of 64 slave ID addresses. The MAX7312 supports hot insertion. All port pins, the INT output, SDA, SCL, and the slave address inputs AD0-2 remain high impedance in power-down (Vt = 0V) up to 6V. The MAX7312 is available in 24-pin SO, SSOP, TSSOP, and thin QFN packages and is specified over the -40°C to +125°C automotive temperature range. For applications requiring I/Os with integrated 100kΩ pullup resistors, refer to the MAX7311 data sheet. Applications include Servers/Blades, RAID Systems, Medical Equipment, Instrumentation and Test Measurement, Networking.
The MAX7312 is a 2‑wire‑interfaced 16‑bit I/O port expander that provides parallel input/output expansion for SMBus™ and I²C applications. It includes input, output, polarity‑inversion, configuration and bus‑timeout registers, and supports hot insertion with all pins high‑impedance in power‑down.
Key features include a 400 kbps I²C‑compatible serial interface, operation from 2 V to 5.5 V, 64 selectable slave IDs, open‑drain interrupt output, low standby current, and availability in 24‑pin SO, SSOP, TSSOP and thin QFN packages.
| Supply Voltage (V+) | 2 V to 5.5 V |
|---|---|
| Operating Temperature Range | -40 °C to +125 °C |
| Low‑Level Output Voltage (VOL) at ISINK = 6 mA | 0.4 V |
| Interrupt Output | Open‑Drain |
| Number of I/O Pins | 16 (default inputs on power‑up) |
| Selectable Slave IDs | 64 |
| Package Options | 24‑pin SO, SSOP, TSSOP, Thin QFN |
Yes, the device supports hot insertion.
It provides 16 I/O pins that default to inputs on power‑up.
The serial interface operates up to 400 kbps (400 kHz).
The device can be powered from 2 V to 5.5 V.