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MAX7325
I2C Port Expander with 8 Push-Pull
and 8 Open-Drain I/Os
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 I2C communication to or from
the MAX7325.
The MAX7325 uses two address inputs with four-level
logic to allow 16 I2C slave addresses. The slave
address also determines the power-up logic state for
the I/O ports, and enables or disables internal 40k
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 I2C 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 0.6A (typ) Standby Current
o -40°C to +125°C Temperature Range
19-3807; Rev 1; 9/12
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX7325AEG+
-40°C to +125°C
24 QSOP
MAX7325AEG/V+
-40°C to +125°C
24 QSOP
MAX7325ATG+
-40°C to +125°C
24 TQFN-EP*
(4mm x 4mm)
Typical Application Circuit and Functional Diagram appear
at end of data sheet.
Selector Guide
PART
INPUTS
INTERRUPT
MASK
OPEN-
DRAIN
OUTPUTS
PUSH-PULL
OUTPUTS
MAX7324
8
Yes
—
8
MAX7325
Up to 8
—
Up to 8
8
MAX7326
4
Yes
—
12
MAX7327
Up to 4
—
Up to 4
12
+
Denotes a lead(Pb)-free/RoHS-compliant package.
*
EP = Exposed paddle.
/V Denotes an automotive qualified part.
TQFN (4mm x 4mm)
+
TOP VIEW
MAX7325
19
20
21
22
12
3
45
6
18
17
16
15
14
13
23
24
12
11
10
9
8
7
SCL
V+
SDA
INT
AD2
P0
P1
P2
P3
P4
P5
AD0
O15
O13
O12
O11
RST
O10
O8
O9
GND
P6
P7
O14
EXPOSED PADDLE
Pin Configurations
Pin Configurations continued at end of data sheet.