General Description
The MAX7326 2-wire serial-interfaced peripheral fea-
tures 16 I/O ports. The ports are divided into 12 push-
pull 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 inter-
rupt mask to assert the open-drain, +6V-tolerant INT
output. 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 I
2
C communi-
cation to or from the MAX7326.
The MAX7326 uses two address inputs with four-level
logic to allow 16 I
2
C slave addresses. The slave
address also sets the power-up default state for the 12
output ports and enables or disables internal 40kΩ
pullups in groups of two input ports.
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.
Applications
Features
♦ 400kHz I
2
C Serial Interface
♦ +1.71V to +5.5V Operating Voltage
♦ 12 Push-Pull Outputs Rated at 20mA Sink Current
♦ 4 Input Ports with Matchable Latching Transition
Detection
♦ Input Ports are Overvoltage Protected to +6V
♦ Transient Changes are Latched, Allowing
Detection Between Read Operations
♦ INT Output Alerts Change on Any Selection of
Inputs
♦ AD0 and AD2 Inputs Select from 16 Slave
Addresses
♦ Low 0.6µA Standby Current
♦ -40°C to +125°C Temperature Range
MAX7326
I
2
C Port Expander with 12 Push-Pull Outputs
and 4 Inputs
________________________________________________________________ Maxim Integrated Products 1
19-3804; Rev 0; 10/06
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
EVALUATION KIT
AVAILABLE
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