Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsInterface ICsInterface IC - I/O extensions POR I²C 400 kHz QSOP 24

Typical Application Circuit and Functional Diagram appear

at end of data sheet.

Pin Configurations continued at end of data sheet.

● Cell Phones

● SAN/NAS

● Servers

● Notebooks

● Satellite Radio

General Description

The MAX7324 2-wire serial-interfaced peripheral features

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 combination

of inputs can be selected using the interrupt mask to

assert the INT output. When the MAX7324 is subsequently

accessed through the serial interface, any pending inter-

rupt 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

C communication to or from

the MAX7324.

The MAX7324 uses two address inputs with four-level

logic to allow 16 I

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.

Applications

Features

● 400kHz, +6V-Tolerant I

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

+Denotes a lead(Pb)-free/RoHS-compliant package.

*EP = Exposed pad.

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

PART TEMP RANGE

PIN-

PACKAGE

MAX7324AEG+ -40°C to +125°C 24 QSOP

MAX7324ATG+ -40°C to +125°C

24 TQFN-EP*

(4mm x 4mm)

TQFN (4mm x 4mm)

TOP VIEW

MAX7324

1 2 3 4 5 6

18 17 16 15 14 13

SCL

V+

SDA

INT

AD2

AD0

O15

O13

O12

RST

O11

O10

GND

O14

EXPOSED PAD

MAX7324 I

C Port Expander with

Eight Push-Pull Outputs and Eight Inputs

19-3785; Rev 1; 5/14

Selector Guide

Ordering Information

Pin Congurations

EVALUATION KIT AVAILABLE

Summary of content (18 pages)

PAGE 1
EVALUATION KIT AVAILABLE I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 General Description The MAX7324 2-wire serial-interfaced peripheral features 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).
PAGE 2
I2C 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..................................................
PAGE 3
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Port and Interrupt INT Timing Characteristics (V+ = +1.71V to +5.5V, TA = -40°C to +125°C, unless otherwise noted. Typical values are at V+ = +3.3V, TA = +25°C.
PAGE 4
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Typical Operating Characteristics (TA = +25°C, unless otherwise noted.) 1.4 1.2 V+ = +5.0V 1.0 0.6 0.4 OUTPUT-VOLTAGE LOW vs. TEMPERATURE 0.20 V+ = +3.3V ISINK = 15mA 0.15 V+ = +5.0V ISINK = 20mA 0.10 V+ = +2.5V ISINK = 10mA 0.05 0 V+ = +1.71V ISINK = 5mA -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) MAX7324 toc02 40 30 V+ = +3.3V 20 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) 0.
PAGE 5
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Detailed Description MAX7324–MAX7327 Family Comparison The MAX7324–MAX7327 family consists of four pin-compatible, 16-port expanders that integrate the function of the MAX7320 and one of either the MAX7319, MAX7321, MAX7322, or MAX7323. Functional Overview The MAX7324 is a general-purpose port expander operating from a +1.71V to +5.
PAGE 6
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Table 1. MAX7319–MAX7329 Family Comparison (continued) PART I2C INPUT SLAVE INPUTS INTERRUPT ADDRESS MASK OPENDRAIN OUTPUTS PUSHPULL OUTPUTS CONFIGURATION 4 input-only, 12 push-pull output versions: 4 input ports with programmable latching transition detection interrupt and selectable pullups. MAX7326 4 Yes — 12 101xxxx and 110xxxx 12 push-pull outputs with selectable default logic levels.
PAGE 7
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Table 1. MAX7319–MAX7329 Family Comparison (continued) PART I2C INPUT SLAVE INPUTS INTERRUPT ADDRESS MASK MAX7323 110xxxx Up to 4 — OPENDRAIN OUTPUTS Up to 4 PUSHPULL OUTPUTS 4 CONFIGURATION 4 I/O, 4 output-only versions: 4 open-drain I/O ports with latching transition detection interrupt and selectable pullups. 4 push-pull outputs with selectable power-up default levels.
PAGE 8
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Table 2.
PAGE 9
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Table 3.
PAGE 10
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Serial Interface Serial Addressing The MAX7324 operates as a slave that sends and receives data through an I2C interface. The interface uses a serial-data line (SDA) and a serial-clock line (SCL) to achieve bidirectional communication between master(s) and slave(s). The master initiates all data transfers to and from the MAX7324 and generates the SCL clock that synchronizes the data transfer (Figure 1).
PAGE 11
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Acknowledge The first (A6), second (A5), and third (A4) bits of the MAX7324 slave address are always 1, 1, and 0 (I0–I7) or 1, 0, and 1 (O8–O15). Connect AD0 and AD2 to GND, V+, SDA, or SCL to select the slave address bits A3, A2, A1, and A0. The MAX7324 has 16 possible slave address pairs (Tables 2 and 3), allowing up to 16 MAX7324 devices on an I2C bus.
PAGE 12
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Reading from the MAX7324 If a port input data change occurs during the read sequence, INT is reasserted during the I2C STOP bit. The MAX7324 does not generate another interrupt during a single-byte or multibyte read. Input-port data is sampled during the preceding I2C acknowledge bit (the acknowledge bit for the I2C slave address in the case of a single-byte or 2-byte read).
PAGE 13
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 When the master reads 2 bytes from the output ports of the MAX7324 and subsequently issues a STOP condition (Figure 7), the MAX7324 transmits the current port data, followed by the transition flags. The transition flags are then cleared, and transition detection is reset. INT deasserts during the slave acknowledge.
PAGE 14
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Writing to the MAX7324 A write to the input ports of the MAX7324 starts with the master transmitting the group's slave address with the R/W bit set low. The MAX7324 acknowledges the slave address and samples the ports during the acknowledge bit. INT deasserts during the slave acknowledge. The master can now transmit one or more bytes of data.
PAGE 15
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Applications Information Port Input and I2C Interface Level Translation from Higher or Lower Logic Voltages SDA, SCL, AD0, AD2, RST, INT, and I0–I7 are overvoltage protected to +6V. This allows the MAX7324 to operate from a lower supply voltage, such as +3.3V, while the I2C interface and/or any of the eight input ports are driven from a higher logic level, such as +5V.
PAGE 16
MAX7324 Set the port output low to light the LED. Choose the resistor value according to the following formula: RLED = (VSUPPLY - VLED - VOL) / ILED where: RLED is the resistance of the resistor in series with the LED (Ω). VSUPPLY is the supply voltage used to drive the LED (V). VLED is the forward voltage of the LED (V). VOL is the output low voltage of the MAX7324 when sinking ILED (V). ILED is the desired operating current of the LED (A). For example, to operate a 2.
PAGE 17
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Functional Diagram Typical Application Circuit 3.
PAGE 18
I2C Port Expander with Eight Push-Pull Outputs and Eight Inputs MAX7324 Revision History REVISION NUMBER REVISION DATE PAGES CHANGED 0 10/06 Initial release — 1 5/14 No /V OPNs; removed automotive reference from Applications section; updated Packaging Information 1 DESCRIPTION For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.