19-3806; Rev 1; 7/07
I
2
C Port Expander with 4 Push-Pull Outputs
and 4 Open-Drain I/Os
General Description
The MAX7323 2-wire serial-interfaced peripheral fea-
tures eight I/O ports. Four ports are push-pull outputs
and the other four are open-drain I/O ports, indepen-
dent of supply voltage.
The four I/O ports configured as inputs are continu-
ously monitored for state changes (transition detec-
tion). State changes are indicated by the open-drain
INT
output. The interrupt is latched, allowing detection
of transient changes. When the MAX7323 is subse-
quently accessed through the serial interface, any
pending interrupt is cleared.
The four push-pull and four 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 MAX7323.
The MAX7323 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 for the input ports in groups of two ports.
The MAX7323 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 MAX7323 is available in 16-pin QSOP and 16-pin
TQFN packages, and is specified over the automotive
temperature range (-40°C to +125°C).
Features
♦
400kHz I
2
C Serial Interface
♦
+1.71V to +5.5V Operating Voltage
♦
4 Push-Pull Output Ports Rated at 20mA Sink
Current
♦
4 Open-Drain I/O Ports Rated to 20mA Sink Current
♦
4 I/O Ports Are Overvoltage Protected to +6V
♦
Transient Changes Are Latched, Allowing Detection
Between Read Operations
♦
INT
Output Alerts Change on Inputs
♦
AD0 and AD2 Inputs Select from 16 Slave
Addresses
♦
Low 0.6µA (typ) Standby Current
♦
-40°C to +125°C Operating Temperature Range
MAX7323
Ordering Information
PART
MAX7323AEE+
MAX7323ATE+
TEMP
RANGE
-40°C to
+125°C
-40°C to
+125°C
PIN-
PACKAGE
16 QSOP
16 TQFN-EP*
3mm x 3mm
TOP
MARK
—
ADE
PKG
CODE
E16-4
T1633-4
Applications
Cell Phones
SAN/NAS
Servers
Notebooks
RAID
Automotive
+Denotes
a lead-free package.
*EP
= Exposed paddle.
Selector Guide
PART
MAX7319
MAX7320
INTERRUPT
INPUTS
MASK
8
—
Up to 8
4
Up to 4
Up to 8
Up to 8
Yes
—
—
Yes
—
—
—
OPEN-
PUSH-PULL
DRAIN
OUTPUTS
OUTPUTS
—
—
Up to 8
—
Up to 4
Up to 8
Up to 8
—
8
—
4
4
—
—
Typical Application Circuit
3.3V
0.047μF
μC
SCL
SDA
RST
INT
SCL
SDA
RST
INT
AD0
AD2
V+
MAX7321
MAX7322
OUTPUT
OUTPUT
I/O
I/O
I/O
I/O
OUTPUT
OUTPUT
MAX7323
O7
O6
P5
P4
P3
P2
O1
O0
MAX7323
MAX7328
MAX7329
GND
Pin Configurations and Functional Diagram appear at end
of data sheet.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
I
2
C Port Expander with 4 Push-Pull Outputs
and 4 Open-Drain I/Os
MAX7323
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
Supply Voltage V+....................................................-0.3V to +6V
SCL, SDA, AD0, AD2,
RST, INT,
P2–P5 ...................-0.3V to +6V
O0, O1, O6, O7...............................................-0.3 to (V+ + 0.3V)
O0, O1, O6, O7 Output Current........................................±25mA
P2–P5 Sink Current...........................................................±25mA
SDA Sink Current ............................................................... 10mA
INT
Sink Current..................................................................10mA
Total V+ Current..................................................................50mA
Total GND Current ...........................................................100mA
Continuous Power Dissipation (T
A
= +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW
16-Pin TQFN (derate 15.6mW/°C above +70°C) .......1250mW
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.
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,
P2–P5
Input Low Voltage
SDA, SCL, AD0, AD2,
RST,
P2–P5
Input Leakage Current
SDA, SCL, AD0, AD2,
RST,
P2–P5
Input Capacitance
SDA, SCL, AD0, AD2,
RST,
P2–P5
V+ = +1.71V, I
SINK
= 5mA
Output Low Voltage
O0, O1, O6, O7, P2–P5
V
OL
V+ = +2.5V, I
SINK
= 10mA
V+ = +3.3V, I
SINK
= 15mA
V+ = +5V, I
SINK
= 20mA
V+ = +1.71V, I
SOURCE
= 2mA
Output High Voltage
O0, O1, O6, O7
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
V+ - 250
V+ - 360
V+ - 260
V+ - 350
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+
≥
1.8V
SDA, SCL, AD0, AD2,
RST,
P2–P5 at V+ or
GND, internal pullup disabled
-0.2
10
105
131
154
160
V+ - 30
V+ - 70
V+ - 100
V+ - 120
250
250
55
mV
mV
kΩ
mV
180
240
290
310
mV
0.8 x V+
0.7 x V+
0.2 x V+
0.3 x V+
+0.2
0.6
23
CONDITIONS
MIN
1.71
TYP
MAX
5.50
1.6
1.5
55
UNITS
V
V
µA
µA
V
V
µA
pF
2
_______________________________________________________________________________________
I
2
C Port Expander with 4 Push-Pull Outputs
and 4 Open-Drain I/Os
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
MAX7323
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 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) in order 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+ with 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 4 Push-Pull Outputs
and 4 Open-Drain I/Os
MAX7323
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
STANDBY CURRENT vs. TEMPERATURE
MAX7323 toc01
SUPPLY CURRENT vs. TEMPERATURE
f
SCL
= 400kHz
50
SUPPLY CURRENT (μA)
40
30
20
10
V+ = +1.71V
0
V+ = +3.3V
V+ = +5.0V
MAX7323 toc02
MAX7323 toc04
2.0
1.8
STANDBY CURRENT (μA)
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
V+ = +2.5V
V+ = +3.3V
60
f
SCL
= 0kHz
V+ = +5.0V
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
MAX7323 toc03
OUTPUT VOLTAGE HIGH
vs. TEMPERATURE
6
5
OUTPUT VOLTAGE HIGH (V)
4
3
2
1
0
V+ = +1.71V
V+ = +2.5V
I
SOURCE
= 2mA I
SOURCE
= 5mA
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
V+ = +3.3V
I
SOURCE
= 15mA
V+ = +5.0V
I
SOURCE
= 20mA
0.40
0.35
OUTPUT VOLTAGE LOW (V)
0.30
0.25
0.20
0.15
0.10
0.05
0
V+ = +1.71V
I
SINK
= 5mA
V+ = +3.3V
I
SINK
= 15mA
V+ = +2.5V
I
SINK
= 10mA
V+ = +5.0V
I
SINK
= 20mA
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
Pin Description
PIN
QSOP
1, 3
2
4, 5, 11, 12
6, 7, 9, 10
8
13
14
15
16
—
TQFN
15, 1
16
2, 3, 9, 10
4, 5, 7, 8
6
11
12
13
14
EP
NAME
AD0,
AD2
RST
FUNCTION
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 Table 3).
Reset Input, Active Low. Drive
RST
low to clear the 2-wire interface.
O0, O1,
Output Ports. O0, O1, O6, and O7 are push-pull outputs.
O6, O7
P2–P5
GND
INT
SCL
SDA
V+
EP
I/O Ports. P2 to P5 are open-drain I/Os rated to +6V, 20mA.
Ground
Interrupt Output.
INT
is an open-drain output.
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 as close to the device as possible.
Exposed Pad. Connect exposed pad to GND.
4
_______________________________________________________________________________________
I
2
C Port Expander with 4 Push-Pull Outputs
and 4 Open-Drain I/Os
Detailed Description
MAX7319–MAX7329 Family Comparison
The MAX7319–MAX7323 family consists of five pin-
compatible, eight-port expanders. Each version is opti-
mized for different applications. The MAX7328 and
MAX7329 are industry-standard parts.
The MAX7324–MAX7327 family consists of four pin-
compatible, 16-port expanders that integrate the func-
tions of the MAX7320 and one of either the MAX7319,
MAX7321, MAX7322, or MAX7323.
Functional Overview
The MAX7323 is a general-purpose port expander, oper-
ating from a +1.71V to +5.5V supply, that provides four
push-pull output ports with 20mA sink, 10mA source drive
capability, and four open-drain I/O ports with a 20mA sink
capability. The four open-drain outputs are overvoltage
protected to +6V independent of supply voltage.
The MAX7323 is set to one of 16 I
2
C slave addresses
(0x60 to 0x6F) using the address select inputs AD0 and
AD2, and is accessed over an I
2
C serial interface up to
400kHz. The
RST
input clears the serial interface in
case of a bus lockup, terminating any serial transaction
to or from the MAX7323.
MAX7323
Table 1. MAX7319–MAX7329 Family Comparison
PART
I
2
C
SLAVE
INPUTS
ADDRESS
INPUT
INTERRUPT
MASK
OPEN-
DRAIN
OUTPUTS
PUSH-
PULL
OUTPUTS
APPLICATION
8-PORT EXPANDERS
Input-only versions:
8 input ports with programmable latching transition
detection interrupt and selectable pullups.
MAX7319
110xxxx
8
Yes
—
—
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
momentarily) since the ports were last read.
Output-only versions:
8 push-pull outputs with selectable power-up default
levels.
Push-pull outputs offer faster rise time than open-
drain outputs, and require no pullup resistors.
I/O versions:
8 open-drain I/O ports with latching transition
detection interrupt and selectable pullups.
MAX7321
110xxxx
Up to 8
—
Up to 8
—
Open-drain outputs can level shift the logic-high
state to a higher or lower voltage than V+ using
external pullup resistors. Any port can be used as an
input by setting the open-drain output to logic-high.
Transition flags identify which inputs have changed
(even momentarily) since the ports were last read.
4 input-only, 4 output-only versions:
4 input ports with programmable latching transition
detection interrupt and selectable pullups;
4 push-pull outputs with selectable power-up default
levels.
MAX7320
101xxxx
—
—
—
8
MAX7322
110xxxx
4
Yes
—
4
_______________________________________________________________________________________
5
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