MAX7327 Datasheet, PDF (1/21 Pages) Maxim Integrated Products – I2C Port Expander with 12 Push-Pull Outputs and 4 Open-Drain I/Os

19-3805; Rev 0; 8/06
I²C Port Expander with 12 Push-Pull Outputs
and 4 Open-Drain I/Os
General Description
The MAX7327, a 2-wire serial-interfaced peripheral,
features 12 push-pull outputs and four configurable
open-drain I/O ports with selectable internal pullups
and transition detection. Ports are overvoltage protect-
ed to +6V, independent of supply voltage.
The four I/O ports configured as inputs are continuously
monitored for state changes (transition detection). State
changes are indicated by the open-drain, +6V-tolerant
INT output. The interrupt is latched, detecting transient
changes. When the MAX7327 is subsequently accessed
through the serial interface, any pending interrupt is
cleared. The 12 push-pull and the four open-drain out-
puts are rated to sink 20mA, and are capable of driving
LEDs. The RST input clears the serial interface, terminat-
ing any I²C* communication to or from the MAX7327.
The MAX7327 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 40kΩ
pullups in groups of two ports.
The MAX7327 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 MAX7327 is available in the 24-pin QSOP and
TQFN packages, and is specified over the -40°C to
+125°C automotive temperature range.
Applications
Cell Phones
SAN/NAS
Notebooks
Satellite Radio
Servers
Automotive
Pin Configurations
TOP VIEW
18 17 16 15 14 13
SCL 19
12 O10
SDA 20
11 O9
V+ 21
INT 22
MAX7327
10 O8
9 GND
RST 23
AD2 24
EXPOSED PADDLE
8 O7
7 O6
12 3456
TQFN (4mm x 4mm)
Pin Configurations continued at end of data sheet.
Features
♦ 400kHz I²C Serial Interface
♦ +1.71V to +5.5V Operating Voltage
♦ 12 Push-Pull Output Ports, Rated at 20mA Sink
Current
♦ 4 Open-Drain I/O Ports, Rated at 20mA Sink Current
♦ I/O Ports are Overvoltage Protected to +6V
♦ Selectable I/O Port Power-Up Default Logic States
♦ Transient Changes are Latched, Allowing Detection
Between Read Operations
♦ INT Output Alerts Changes on Inputs
♦ AD0 and AD2 Inputs Select from 16 Slave
Addresses
♦ Low 0.6µA (typ) Standby Current
♦ -40°C to +125°C Temperature Range
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
PKG
CODE
MAX7327AEG+ -40°C to +125°C 24 QSOP
E24-1
MAX7327ATG+ -40°C to +125°C ^{24 TQFN-EP**}
(4mm x 4mm)
T2444-3
MAX7327AATG+ -40°C to +125°C ^{24 TQFN-EP**} T243A3-1
(3.5mm x 3.5mm)
+Denotes lead-free package.
**EP = Exposed pad.
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
Typical Application Circuit and Functional Diagram appear
at end of data sheet.
*Purchase of I²C components from Maxim Integrated Products,
Inc., or one of its sublicensed Associated Companies, conveys
a license under the Philips I²C Patent Rights to use these com-
ponents in an I²C system, provided that the system conforms
to the I²C Standard Specification as defined by Philips.
________________________________________________________________ Maxim Integrated Products 1
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