19-3056; Rev 3; 1/05
KIT
ATION
EVALU
ABLE
AVAIL
8-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
General Description
The MAX7315 I
2
C-/SMBus-compatible serial interfaced
peripheral provides microprocessors with 8 I/O ports.
Each I/O port can be individually configured as either an
open-drain current-sinking output rated at 50mA at 5.5V,
or a logic input with transition detection. A ninth port can
be used for transition detection interrupt or as a general-
purpose output. The outputs are capable of directly dri-
ving LEDs, or providing logic outputs with external
resistive pullup up to 5.5V.
PWM current drive is integrated with 8 bits of control.
Four bits are global control and apply to all LED outputs
to provide coarse adjustment of current from fully off to
fully on in 14 intensity steps. Each output then has indi-
vidual 4-bit control, which further divides the globally
set current into 16 more steps. Alternatively, the current
control can be configured as a single 8-bit control that
sets all outputs at once.
The MAX7315 is pin and software compatible with the
PCA9534 and PCA9554(A).
Each output has independent blink timing with two blink
phases. All LEDs can be individually set to be on or off
during either blink phase, or to ignore the blink control.
The blink period is controlled by a register.
The MAX7315 supports hot insertion. All port pins, the
INT
output, SDA, SCL, and the slave address inputs ADO-2
remain high impedance in power-down (V+ = 0V) with up
to 6V asserted upon them.
The MAX7315 is controlled through the 2-wire I
2
C/SMBus
serial interface, and can be configured to one of 64 I
2
C
addresses.
Features
o
400kbps, 2-Wire Serial Interface, 5.5V Tolerant
o
2V to 3.6V Operation
o
Overall 8-Bit PWM LED Intensity Control
Global 16-Step Intensity Control
Plus Individual 16-Step Intensity Control
o
Automatic Two-Phase LED Blinking
o
50mA Maximum Port Output Current
o
Supports Hot Insertion
o
Outputs Are 5.5V-Rated Open Drain
o
Inputs Are Overvoltage Protected to 5.5V
o
Transition Detection with Interrupt Output
o
Low Standby Current (1.2µA typ; 3.3µA max)
o
Tiny 3mm x 3mm, Thin QFN Package
o
-40°C to +125°C Temperature Range
o
All Ports Can Be Configured as Inputs or Outputs
MAX7315
Ordering Information
PIN-
TOP
PKG
PACKAGE MARK CODE
16 Thin QFN
MAX7315ATE -40°C to +125°C 3mm x 3mm AAU T1633-4
x 0.8mm
MAX7315AEE -40°C to +125°C 16 QSOP
—
—
PART
TEMP
RANGE
MAX7315AUE -40°C to +125°C 16 TSSOP
—
—
Applications
LCD Backlights
LED Status Indication
Portable Equipment
Laptop Computers
Keypad Backlights
RGB LED Drivers
Cellular Phones
SDA
V+
ADO
13
14
SCL
TOP VIEW
Pin Configurations
INT/O8
P7
10
P6
12
11
9
8
7
P5
P4
GND
P3
MAX7315ATE
15
16
1
AD2
2
P0
6
5
3
P1
4
P2
Typical Application Circuit appears at end of data sheet.
AD1
THIN QFN
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.
8-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
MAX7315
ABSOLUTE MAXIMUM RATINGS
Voltage (with respect to GND)
V+ .............................................................................-0.3V to +4V
SCL, SDA, AD0, AD1, AD2, P0–P7 ..........................-0.3V to +6V
INT/O8
.....................................................................-0.3V to +8V
DC Current on P0–P7,
INT/O8
............................................55mA
DC Current on SDA.............................................................10mA
Maximum GND Current ....................................................190mA
Continuous Power Dissipation (T
A
= +70°C)
16-Pin TSSOP (derate 9.4mW/°C over +70°C) ............754mW
16-Pin QSOP (derate 8.3mW/°C over +70°C)..............666mW
16-Pin QFN (derate 14.7mW/°C over +70°C) ............1176mW
Operating Temperature Range (TMIN to TMAX)-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
(Typical Operating Circuit, V+ = 2V to 3.6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, T
A
= +25°C.)
(Note 1)
PARAMETER
Operating Supply Voltage
Output Load External Supply
Voltage
Standby Current
(Interface Idle, PWM Disabled)
SYMBOL
V+
V
EXT
SCL and SDA at V+; other
digital inputs at V+ or GND;
PWM intensity control disabled
SCL and SDA at V+; other
digital inputs at V+ or GND;
PWM intensity control enabled
f
SCL
= 400kHz; other digital
inputs at V+ or GND; PWM
intensity control disabled
f
SCL
= 400kHz; other digital
inputs at V+ or GND; PWM
intensity control enabled
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
0.7
V+
51
40
7
CONDITIONS
MIN
2
0
1.2
TYP
MAX
3.6
5.5
2.3
2.6
3.3
12.1
13.5
14.4
76
78
80
110
117
122
V
µA
µA
µA
µA
UNITS
V
V
I
+
Supply Current
(Interface Idle, PWM Enabled)
Supply Current
(Interface Running, PWM
Disabled)
Supply Current
(Interface Running, PWM
Enabled)
Input High Voltage
SDA, SCL, AD0, AD1, AD2,
P0–P7
Input Low Voltage
SDA, SCL, AD0, AD1, AD2,
P0–P7
Input Leakage Current
SDA, SCL, AD0, AD1, AD2,
P0–P7
Input Capacitance
SDA, SCL, AD0, AD1, AD2,
P0–P7
I
+
I
+
I
+
V
IH
V
IL
0.3
V+
V
I
IH
, I
IL
Input = GND or V+
-0.2
+0.2
µA
8
pF
2
_______________________________________________________________________________________
8-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
ELECTRICAL CHARACTERISTICS (continued)
(Typical Operating Circuit, V+ = 2V to 3.6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, T
A
= + 25°C.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
T
A
= +25°C
V+ = 2V, I
SINK
= 20mA
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
Output Low Voltage
P0–P7,
INT/O8
V
OL
V+ = 2.5V, I
SINK
= 20mA
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
T
A
= +25°C
V+ = 3.3V, I
SINK
= 20mA
Output Low-Voltage SDA
PWM Clock Frequency
V
OLSDA
f
PWM
I
SINK
= 6mA
32
T
A
= -40°C to +85°C
T
A
= T
MIN
to T
MAX
0.12
0.13
MIN
TYP
0.15
MAX
0.25
0.29
0.31
0.22
0.25
0.27
0.22
0.23
0.25
0.4
V
kHz
V
UNITS
MAX7315
TIMING CHARACTERISTICS
(Typical Operating Circuit, V+ = 2V to 3.6V, T
A
= T
MIN
to T
MAX
, 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
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
(Notes 3, 4)
(Notes 3, 4)
(Notes 3, 5)
(Note 6)
(Note 3)
(Note 2)
180
1.3
0.7
200 +
0.1C
b
200 +
0.1C
b
200 +
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
_______________________________________________________________________________________
3
8-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
MAX7315
TIMING CHARACTERISTICS (continued)
(Typical Operating Circuit, V+ = 2V to 3.6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, T
A
= +25°C.)
(Note 1)
PARAMETER
Interrupt Valid
Interrupt Reset
Output Data Valid
Input Data Setup Time
Input Data Hold Time
SYMBOL
t
IV
t
IR
t
DV
t
DS
t
DH
CONDITIONS
Figure 10
Figure 10
Figure 10
Figure 10
Figure 10
100
1
MIN
TYP
MAX
6.5
1
5
UNITS
µs
µs
µs
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) 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
DD
and 0.7 x V
DD
.
Note 5:
I
SINK
≤
6mA. C
b
= total capacitance of one bus line in pF. t
R
and t
F
measured between 0.3 x V
DD
and 0.7 x V
DD
.
Note 6:
Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns.
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. TEMPERATURE
(PWM DISABLED; f
SCL
= 400kHz)
MAX7315 toc01
MAX7315 toc02
STANDBY CURRENT vs. TEMPERATURE
10
9
8
STANDBY CURRENT (µA)
7
6
5
4
3
2
1
0
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
V+ = 2V
PWM ENABLED
V+ = 2.7V
V+ = 3.6V
PWM ENABLED
PWM
V+ = 2V
V+ = 2.7V
PWM DISABLED PWM DISABLED DISABLED
V+ = 3.6V
PWM ENABLED
70
60
SUPPLY CURRENT (µA)
50
40
SUPPLY CURRENT vs. TEMPERATURE
(PWM ENABLED; f
SCL
= 400kHz)
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
MAX7315 toc03
V+ = 3.6V
SUPPLY CURRENT (µA)
V+ = 3.6V
V+ = 2.7V
V+ = 2V
V+ = 2.7V
30
20
10
0
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
V+ = 2V
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
4
_______________________________________________________________________________________
8-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
MAX7315
Typical Operating Characteristics (continued)
(T
A
= +25°C, unless otherwise noted.)
PORT OUTPUT LOW VOLTAGE WITH 50mA
LOAD CURRENT vs. TEMPERATURE
MAX7315 toc04
PORT OUTPUT LOW VOLTAGE WITH 20mA
LOAD CURRENT vs. TEMPERATURE
ALL OUTPUTS LOADED
PORT OUTPUT LOW VOLTAGE V
OL
(V)
0.5
0.4
0.3
0.2
0.1
0
MAX7315 toc05
PWM CLOCK FREQUENCY
vs. TEMPERATURE
MAX7315 toc06
0.6
PORT OUTPUT LOW VOLTAGE V
OL
(V)
0.5
V+ = 2.7V
0.4
0.3
0.2
0.1
0
V+ = 3.6V
V+ = 2V
0.6
1.050
1.025
PWM CLOCK FREQUENCY
1.000
0.975
V+ = 2.7V
0.950
0.925
0.900
NORMALIZED TO V+ = 3.3V, T
A
= +25°C
V+ = 2V
V+ = 3.6V
V+ = 2V
V+ = 2.7V
V+ = 3.6V
-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)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
SCOPE SHOT OF 2 OUTPUT PORTS
MAX7315 toc07
SCOPE SHOT OF 2 OUTPUT PORTS
MAX7315 toc08
SINK CURRENT vs. V
OL
MAX7315 toc09
0.35
OUTPUT 1,
2V/div
0.30
0.25
V+ = 2.7V
V
OL
(V)
0.20
V+ = 3.3V
0.15
V+ = 3.6V
0.10
0.05
ONLY ONE OUTPUT LOADED
0
MASTER INTENSITY SET TO 1/15
OUTPUT 1,
2V/div
OUTPUT 1 INDIVIDUAL INTENSITY
SET TO 1/16
MASTER INTENSITY SET TO 14/15
V+ = 2V
OUTPUT 1 INDIVIDUAL INTENSITY
SET TO 1/16
OUTPUT 2,
2V/div
OUTPUT 2 INDIVIDUAL INTENSITY
SET TO 15/16
OUTPUT 2 INDIVIDUAL INTENSITY
SET TO 14/15
OUTPUT 2,
2V/div
2ms/div
2ms/div
0
10
20
30
40
50
SINK CURRENT (mA)
_______________________________________________________________________________________
5
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