EVALUATION KIT AVAILABLE
General Description
The MAX7325 2-wire serial-interfaced peripheral features
16 I/O ports. Ports are divided into eight push-pull out-
puts and eight I/Os with selectable internal pullups and
transition detection. Eight ports are push-pull outputs
and eight I/Os may be used as a logic input or an open-
drain output. Ports are overvoltage protected to +6V.
All I/O ports configured as inputs are continuously mon-
itored for state changes (transition detection). State
changes are indicated by the INT output. The interrupt
is latched, allowing detection of transient changes.
When the MAX7325 is subsequently accessed through
the serial interface, any pending interrupt is cleared.
The open-drain outputs are rated to sink 20mA, and are
capable of driving LEDs. The RST input clears the serial
interface, terminating any I
2
C communication to or from
the MAX7325.
The MAX7325 uses two address inputs with four-level
logic to allow 16 I
2
C slave addresses. The slave
address also determines the power-up logic state for
the I/O ports, and enables or disables internal 40kΩ
pullups in groups of four ports.
The MAX7325 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 MAX7325 is available in 24-pin QSOP and TQFN
packages and is specified over the -40°C to +125°C
automotive temperature range.
Applications
Cell Phones Notebooks
SAN/NAS Satellite Radio
Servers Automotive
Features
o 400kHz I
2
C Serial Interface
o +1.71V to +5.5V Operation
o 8 Push-Pull Outputs
o 8 Open-Drain I/O Ports, Rated to 20mA Sink
Current
o I/O Ports are Overvoltage Protected to +6V
o Selectable I/O Port Power-Up Default Logic States
o Transient Changes are Latched, Allowing
Detection Between Read Operations
o INT Output Alerts Change on Inputs
o AD0 and AD2 Inputs Select from 16 Slave
Addresses
o Low 0.6µA (typ) Standby Current
o -40°C to +125°C Temperature Range
19-3807; Rev 1; 9/12
Ordering Information