MAX7326

The MAX7326 uses two address inputs with four-level logic to allow 16 I2C slave addresses. The slave address also sets the power-up default state for the 12 output ports and enables or disables internal 40k pullups in groups of two input ports. The MAX7326 2-wire serial-interfaced peripheral features 16 I/O ports. When the MAX7326 is subsequently accessed through the serial interface, any pending interrupt is cleared. The 12 push-pull outputs are rated to sink 20mA and are capable of driving LEDs. The RST input clears the serial interace, terminating any I2C communication to or from the MAX7326. The ports are divided into 12 pushpull outputs and four input ports with selectable internal pullups. Input ports are overvoltage protected to +6V and feature transition detection with interrupt output. The four input ports are continuously monitored for state changes (transition detection). The interrupt is latched, allowing detection of transient changes. Any combination of inputs can be selected using the interrupt mask to assert the open-drain, +6V-tolerant INT output. The MAX7326 is one device in a family of pin-compatible port expanders with a choice of input ports, open-drain I/O ports, and push-pull output ports (see Table 1). The MAX7326 is available in 24-pin QSOP and TQFN packages and is specified over the -40°C to +125°C automotive temperature range.

The features of MAX7326 can be summarized as (1)400kHz I2C serial interface; (2)+1.71V to +5.5V operating voltage; (3)12 push-pull outputs rated at 20mA sink current; (4)4 input ports with matchable latching transition detection; (5)input ports are overvoltage protected to +6V; (6)transient changes are latched, allowing detection between read operations; (7)INT output alerts change on any selection of inputs; (8)AD0 and AD2 inputs select from 16 slave addresses; (9)low 0.6A standby current; (10)-40°C to +125°C temperature Range.

The absolute maximum ratings of MAX7326 are (1)(All voltages referenced to GND.)supply voltage V+: -0.3V to +6V; (2)SCL, SDA, AD0, AD2, RST, INT, I2I5: -0.3V to +6V; (3)O0, O1, O6O15: -0.3V to V+ + 0.3V; (4)O0, O1, O6O15 output current: ±25mA; (5)SDA sink current: 10mA; (6)INT sink current: 10mA; (7)total V+ current: 50mA; (8)total GND current: 100mA; (9)continuous power dissipation (TA = +70°C)24-Pin QSOP (derate 9.5mW/°C over +70°C)761.9mW/ 24-Pin TQFN (derate 20.8mW/°C over +70°C): 1666.7mW; (10)operating temperature range: -40°C to +125°C; (11)junction temperature: +150°C; (12)storage temperature range: -65°C to +150°C; (13)lead temperature (soldering, 10s): +300°C.