19-3785; Rev 0; 10/06
I
2
C Port Expander with Eight Push-Pull Outputs
and Eight Inputs
General Description
The MAX7324 2-wire serial-interfaced peripheral fea-
tures 16 I/O ports that are divided into eight push-pull
outputs and eight inputs. Each input features selectable
internal pullups, overvoltage protection to +6V, and
transition detection with an interrupt output.
All input ports are continuously monitored for state
changes (transition detection). The interrupt is latched,
allowing detection of transient changes. Any combina-
tion of inputs can be selected using the interrupt mask
to assert the
INT
output. When the MAX7324 is subse-
quently accessed through the serial interface, any
pending interrupt is cleared.
The push-pull 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 MAX7324.
The MAX7324 uses two address inputs with four-level
logic to allow 16 I
2
C slave addresses. The slave
address also enables or disables internal 40kΩ pullups
in groups of four ports.
The MAX7324 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 MAX7324 is available in 24-pin QSOP and TQFN
packages, and is specified over the -40°C to +125°C
automotive temperature range.
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
Features
400kHz, +6V-Tolerant I
2
C Serial Interface
+1.71V to 5.5V Operating Voltage
Eight Push-Pull Outputs
Eight Input Ports with Maskable, 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
MAX7324
Ordering Information
PART
MAX7324AEG+
MAX7324ATG+
TEMP RANGE
-40°C to +125°C
-40°C to +125°C
PIN-
PACKAGE
24 QSOP
24 TQFN-EP*
(4mm x 4mm)
PKG
CODE
E24-1
T2444-3
Applications
Cell Phones
SAN/NAS
Servers
Notebooks
Automotive
Satellite Radio
+Denotes
lead-free package.
*EP
= Exposed paddle.
Selector Guide
PART
MAX7324
MAX7325
INTERRUPT
INPUTS
MASK
8
Up to 8
4
Up to 4
Yes
—
Yes
—
OPEN-
PUSH-PULL
DRAIN
OUTPUTS
OUTPUTS
—
Up to 8
—
Up to 4
8
8
12
12
Pin Configurations
O15
O13
O12
14
O14
O11
13
12 O10
11 O9
10 O8
TOP VIEW
18
SCL 19
SDA 20
V+ 21
INT 22
RST 23
AD2 24
+
1
I0
AD0
17
16
15
MAX7326
MAX7327
MAX7324
EXPOSED PADDLE
2
I1
3
I2
4
I3
5
I4
6
I5
9
8
7
GND
I7
I6
Typical Application Circuit and Functional Diagram appear
at end of data sheet.
TQFN (4mm x 4mm)
Pin Configurations continued at end of data sheet.
________________________________________________________________
Maxim Integrated Products
1
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.
I
2
C Port Expander with Eight Push-Pull Outputs
and Eight Inputs
MAX7324
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
Supply Voltage V+....................................................-0.3V to +6V
SCL, SDA, AD0, AD2,
RST, INT,
I0–I7......................-0.3V to +6V
O8–O15………….…………………………..…-0.3V to (V+ + 0.3V)
O8–O15 Output Current......………………………………...±25mA
SDA Sink Current ............................................................... 10mA
INT
Sink Current..................................................................10mA
Total V+ Current..................................................................50mA
Total GND Current ...........................................................100mA
Continuous Power Dissipation
24-Pin QSOP (derate 9.5mW/°C over T
A
= +70°C) ..761.9mW
24-Pin TQFN (derate 20.8mW/°C over
T
A
= +70°C) ............................................................1666.7mW
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(V+ = +1.71V to +5.5V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V+ = +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER
Operating Supply Voltage
Power-On Reset Voltage
Standby Current (Interface Idle)
Supply Current
(Interface Running)
Input High-Voltage
SDA, SCL, AD0, AD2,
RST,
I0–I7
Input Low-Voltage
SDA, SCL, AD0, AD2,
RST,
I0–I7
Input Leakage Current
SDA, SCL, AD0, AD2,
RST,
I0–I7
Input Capacitance
SDA, SCL, AD0, AD2,
RST,
I0–I7
V+ = +1.71V, I
SINK
= 5mA (QSOP)
V+ = +1.71V, I
SINK
= 5mA (TQFN)
V+ = +2.5V, I
SINK
= 10mA (QSOP)
Output Low Voltage
O8–O15
V
OL
V+ = +2.5V, I
SINK
= 10mA (TQFN)
V+ = +3.3V, I
SINK
= 15mA (QSOP)
V+ = +3.3V, I
SINK
= 15mA (TQFN)
V+ = +5V, I
SINK
= 20mA (QSOP)
V+ = +5V, I
SINK
= 20mA (TQFN)
V+ = +1.71V, I
SOURCE
= 2mA
Output High Voltage
O8–O15
V
OH
V+ = +2.5V, I
SOURCE
= 5mA
V+ = +3.3V, I
SOURCE
= 5mA
V+ = +5V, I
SOURCE
= 10mA
Output Low-Voltage SDA
Output Low-Voltage
INT
Port Input Pullup Resistor
V
OLSDA
V
OLINT
R
PU
I
SINK
= 6mA
I
SINK
= 5mA
25
130
40
SYMBOL
V+
V
POR
I
STB
I+
V
IH
V
IL
I
IH
, I
IL
V+ falling
SCL and SDA and other digital inputs at V+
f
SCL
= 400kHz; other digital inputs at V+
V+ < 1.8V
V+
≥
1.8
V+ < 1.8V
V+
≥
1.8
SDA, SCL, AD0, AD2,
RST,
I0–I7 at V+ or
GND
-0.2
10
90
90
110
110
130
130
140
140
V+ - 250 V+ - 30
V+ - 360 V+ - 70
V+ - 260 V+ - 100
V+ - 360 V+ - 120
250
250
55
mV
mV
kΩ
mV
180
230
210
260
230
280
250
300
mV
0.8 x V+
0.7 x V+
0.2 x V+
0.3 x V+
+0.2
0.6
23
CONDITIONS
T
A
= -40°C to +125°C
MIN
1.71
TYP
MAX
5.50
1.6
1.9
55
UNITS
V
V
µA
µA
V
V
µA
pF
2
_______________________________________________________________________________________
I
2
C Port Expander with Eight Push-Pull Outputs
and Eight Inputs
PORT AND INTERRUPT
INT
TIMING CHARACTERISTICS
(V+ = +1.71V to +5.5V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V+ = +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER
Port-Output Data Valid
Port-Input Setup Time
Port-Input Hold Time
INT
Input Data Valid Time
INT
Reset Delay Time from STOP
INT
Reset Delay Time from
Acknowledge
SYMBOL
t
PPV
t
PSU
t
PH
t
IV
t
IP
t
IR
C
L
≤
100pF
C
L
≤
100pF
C
L
≤
100pF
C
L
≤
100pF
C
L
≤
100pF
C
L
≤
100pF
0
4
4
4
4
CONDITIONS
MIN
TYP
MAX
4
UNITS
µs
µs
µs
µs
µs
µs
MAX7324
TIMING CHARACTERISTICS
(V+ = +1.71V to +5.5V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V+ = +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER
Serial-Clock Frequency
Bus Free Time Between a STOP
and a START Condition
Hold Time (Repeated) START
Condition
Repeated START Condition
Setup Time
STOP Condition Setup Time
Data Hold Time
Data Setup Time
SCL Clock Low Period
SCL Clock High Period
Rise Time of Both SDA and SCL
Signals, Receiving
Fall Time of Both SDA and SCL
Signals, Receiving
Fall Time of SDA Transmitting
Pulse Width of Spike Suppressed
Capacitive Load for Each Bus
Line
RST
Pulse Width
RST
Rising to START Condition
Setup Time
SYMBOL
f
SCL
t
BUF
t
HD,STA
t
SU,STA
t
SU,STO
t
HD,DAT
t
SU,DAT
t
LOW
t
HIGH
t
R
t
F
t
F,TX
t
SP
C
b
t
W
t
RST
(Notes 3, 4)
(Notes 3, 4)
(Notes 3, 4)
(Note 5)
(Note 3)
500
1
(Note 2)
100
1.3
0.7
20 +
0.1C
b
20 +
0.1C
b
20 +
0.1C
b
50
400
300
300
250
1.3
0.6
0.6
0.6
0.9
CONDITIONS
MIN
TYP
MAX
400
UNITS
kHz
µs
µs
µs
µs
µs
ns
µs
µs
ns
ns
ns
ns
pF
ns
µs
Note 1:
All parameters are tested at T
A
= +25°C. Specifications over temperature are guaranteed by design.
Note 2:
A master device must provide a hold time of at least 300ns for the SDA signal (referred to V
IL
of the SCL signal) to bridge
the undefined region of SCL’s falling edge.
Note 3:
Guaranteed by design.
Note 4:
C
b
= total capacitance of one bus line in pF. t
R
and t
F
measured between 0.3 x V+ and 0.7 x V+. I
SINK
≤
6mA.
Note 5:
Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns.
_______________________________________________________________________________________
3
I
2
C Port Expander with Eight Push-Pull Outputs
and Eight Inputs
MAX7324
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
STANDBY CURRENT
vs. TEMPERATURE
MAX7324 toc01
SUPPLY CURRENT
vs. TEMPERATURE
f
SCL
= 400kHz
50
SUPPLY CURRENT (µA)
40
30
20
10
0
V+ = +5.0V
MAX7324 toc02
MAX7324 toc04
2.0
1.8
1.6
STANDBY CURRENT (µA)
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
V+ = +1.71V
V+ = +2.5V
V+ = +3.3V
V+ = +5.0V
f
SCL
= 0kHz
60
V+ = +3.3V
V+ = +2.5V
V+ = +1.71V
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
OUTPUT-VOLTAGE LOW
vs. TEMPERATURE
MAX7324 toc03
OUTPUT-VOLTAGE HIGH
vs. TEMPERATURE
6
5
OUTPUT-VOLTAGE HIGH (V)
4
3
2
1
0
V+ = +3.3V
I
SOURCE
= 5mA
V+ = +2.5V I
SOURCE
= 5mA
V+ = +1.71V I
SOURCE
= 2mA
V+ = +5.0V
I
SOURCE
= 10mA
0.25
V+ = +5.0V
I
SINK
= 20mA
V+ = +3.3V
I
SINK
= 15mA
0.15
OUTPUT-VOLTAGE LOW (V)
0.20
0.10
V+ = +2.5V
I
SINK
= 10mA
V+ = +1.71V
I
SINK
= 5mA
0.05
0
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
Pin Description
PIN
QSOP
1
2
3, 21
4–11
12
13–20
22
23
24
—
TQFN
22
23
24, 18
1–8
9
10–17
19
20
21
EP
NAME
INT
RST
AD2, AD0
I0–I7
GND
08–015
SCL
SDA
V
+
EP
FUNCTION
Active-Low Interrupt Output.
INT
is an open-drain output.
Active-Low Reset Input. Drive
RST
low to clear the 2-wire interface.
Address Inputs. Select device slave address with AD0 and AD2. Connect AD0 and AD2
to either GND, V+, SCL, or SDA to give four logic combinations (see Tables 2 and 3).
Input Ports. I0 to I7 are CMOS-logic inputs.
Ground
Output Ports. O8–O15 are push-pull outputs rated at 20mA.
I
2
C-Compatible Serial Clock Input
I
2
C-Compatible Serial Data I/O
Positive Supply Voltage. Bypass V+ to GND with a ceramic capacitor of at least 0.047µF.
Exposed Paddle. Connect exposed pad to GND.
4
_______________________________________________________________________________________
I
2
C Port Expander with Eight Push-Pull Outputs
and Eight Inputs
Detailed Description
MAX7324–MAX7327 Family Comparison
The MAX7324–MAX7327 family consists of four pin-
compatible, 16-port expanders that integrate the func-
tion of the MAX7320 and one of either the MAX7319,
MAX7321, MAX7322, or MAX7323.
The MAX7324 is set to two of 32 I
2
C slave addresses
(see Tables 2 and 3) using address select inputs AD0
and AD2, and is accessed over an I
2
C serial interface
up to 400kHz. The eight outputs and eight inputs have
different slave addresses. The eight push-pull outputs
have the 101xxxx addresses and the eight inputs have
the adresses with 110xxxx. The
RST
input clears the
serial interface in case of a bus lockup, terminating any
serial transaction to or from the MAX7324.
The input ports offer latching transition detection fea-
ture. All input ports are continuously monitored for
changes. An input change sets 1 of 8 flag bits that
identify the changed input(s). All flags are cleared upon
a subsequent read or write transaction to the MAX7324.
MAX7324
Functional Overview
The MAX7324 is a general-purpose port expander
operating from a +1.71V to +5.5V supply with eight
push-pull outputs and eight CMOS input ports that are
overvoltage protected to +5.5V.
Table 1. MAX7319–MAX7329 Family Comparison
PART
I
2
C
INPUT
SLAVE
INPUTS INTERRUPT
MASK
ADDRESS
OPEN-
DRAIN
OUTPUTS
PUSH-
PULL
OUTPUTS
CONFIGURATION
16-PORT EXPANDERS
8 inputs and 8 push-pull outputs version:
8 input ports with programmable latching transition
detection interrupt and selectable pullups.
8 push-pull outputs with selectable default logic
levels.
Offers maximum versatility for automatic input
monitoring. An interrupt mask selects which inputs
cause an interrupt on transitions, and transition flags
identify which inputs have changed (even if only for
a transient) since the ports were last read.
8 I/O and 8 push-pull outputs version:
8 open-drain I/O ports with latching transition
detection interrupt and selectable pullups.
8 push-pull outputs with selectable default logic
levels.
MAX7325
Up to 8
—
Up to 8
8
Open-drain outputs can level shift the logic-high
state to a higher or lower voltage than V+ using
external pullup resistors, but pullups draw current
when output is low. Any open-drain port can be used
as an input by setting the open-drain output to logic-
high. Transition flags identify which open-drain port
inputs have changed (even if only for a transient)
since the ports were last read.
MAX7324
8
Yes
—
8
101xxxx
and
110xxxx
_______________________________________________________________________________________
5
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