MAX7301
4-Wire-Interfaced, 2.5V to 5.5V,
20-Port and 28-Port I/O Expander
General Description
The MAX7301 compact, serial-interfaced I/O expander
(or general-purpose I/O (GPIO) peripheral) provides
microprocessors with up to 28 ports. Each port is individually user configurable to either a logic input or logic output.
Each port can be configured either as a push-pull logic
output capable of sinking 10mA and sourcing 4.5mA, or
a Schmitt logic input with optional internal pullup. Seven
ports feature configurable transition detection logic, which
generates an interrupt upon change of port logic level.
The MAX7301 is controlled through an SPI-compatible
4-wire serial interface.
The MAX7301AAX and MAX7301ATL have 28 ports and
are available in 36-pin SSOP and 40-pin TQFN packages,
respectively. The MAX7301AAI has 20 ports and is available in a 28-pin SSOP package.
For a 2-wire I2C-interfaced version, refer to the MAX7300
data sheet.
For a pin-compatible port expander with additional
24mA constant-current LED drive capability, refer to the
MAX6957 data sheet.
Applications
●●
●●
●●
●●
●● Low Power Consumption Reduces Power-Supply
Requirements
• 11μA (max) Shutdown Current
Typical Operating Circuit
3V
PINPACKAGE
MAX7301AAI+
-40°C to +125°C
28 SSOP
MAX7301AAX+
-40°C to +125°C
36 SSOP
MAX7301ATL+
-40°C to +125°C
P4 32
P5 30
P6 28
P7 26
36 V+
47nF
39kΩ
DATA IN
DATA OUT
Ordering Information
TEMP RANGE
●● Industry-Standard 4-Wire Interface Simplifies
Expansion of I/O Ports to Up to 28 I/Os Independent
of Microprocessor Architecture
• High-Speed, 26MHz, SPI-/QSPI™-/MICROWIRE®Compatible Serial Interface
• 2.25V to 5.5V Operation
• 20 or 28 I/O Ports Configurable as Push-Pull Logic
Output, Schmitt Logic Input or Schmitt Logic Input
with Internal Pullup
• Logic Transition Detection for Seven I/O Ports
CHIP SELECT
CLOCK IN
White Goods
Gaming Machines
Industrial Controllers
System Monitoring
PART
Benefits and Features
3 GND
2 GND
1
ISET
35
MAX7301
CS
33
SCLK
34
DIN
4
DOUT
P8 5
P9 7
P10 9
P11 11
P12 6
P13 8
P14 10
P15 12
P16 13
P17 14
P18 15
P19 16
P20 17
31 P31
29 P30
27 P29
25 P28
24 P27
P21 18
P22 19
P23 20
23 P26
22 P25
21
P24
40 TQFN-EP*
SSOP
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
QSPI is a trademark of Motorola, Inc.
MICROWIRE is a registered trademark of National
Semiconductor Corp.
19-2438; Rev 8; 4/15
Pin Configurations appear at end of data sheet.
I/O 4
I/O 5
I/O 6
I/O 7
I/O 8
I/O 9
I/O 10
I/O 11
I/O 12
I/O 13
I/O 14
I/O 15
I/O 16
I/O 17
I/O 18
I/O 19
I/O 20
I/O 21
I/O 22
I/O 23
I/O 24
I/O 25
I/O 26
I/O 27
I/O 28
I/O 29
I/O 30
I/O 31
