General Description

eral provides microprocessors with 16 I/O ports plus one

output-only port and one input-only port. Each I/O port

can be individually configured as either an open-drain

current-sinking output rated at 50mA and 5.5V, or a logic

input with transition detection. The output-only port can

be assigned as an interrupt output for transition detec-

tion. The outputs are capable of driving LEDs, or provid-

ing logic outputs with external resistive pullup up to 5.5V.

Eight-bit PWM current control is built in for all 17 output

ports. A 4-bit global control applies to all LED outputs

and provides coarse adjustment of current from fully off

to fully on with 14 intensity steps in between. Each out-

put has an individual 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.

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 clock input (up to 1kHz)

on BLINK or by a register. The BLINK input can also be

used as a logic control to turn the LEDs on and off, or as a

general-purpose input.

The MAX7314 supports hot insertion. All port pins, the

INT output, SDA, SCL, RST, BLINK, and the slave

address input ADO remain high impedance in power-

down (V+ = 0V) with up to 6V asserted upon them.

The MAX7314 is controlled through a 2-wire serial inter-

addresses from only one select pin.

Applications

LCD Backlights

LED Status Indication

Relay Drivers

Keypad Backlights

RGB LED Drivers

System I/O Ports

Features

♦ 400kbps, 2-Wire Serial Interface, 5.5V Tolerant

♦ 2V to 3.6V Operation

♦ Overall 8-Bit PWM LED Intensity Control

Global 16-Step Intensity Control

Individual 16-Step Intensity Controls

♦ 2-Phase LED Blinking

♦ 50mA Maximum Port Output Current

♦ Supports Hot Insertion

♦ Outputs are 5.5V-Rated Open Drain

♦ Inputs are Overvoltage Protected to 5.5V

♦ Transition Detection with Interrupt Output

♦ 1.2µA (typ), 3.6µA (max) Operating Current

♦ Small 4mm x 4mm, Thin QFN Package

♦ -40°C to +125°C Temperature Range

18-Port GPIO with LED Intensity Control,

Interrupt, and Hot-Insertion Protection

________________________________________________________________ Maxim Integrated Products

1

MAX7314

P8

P10

P0

P1

P2

P3

P4

P5

P6

P7

V+

3.3V

µC

SDA

SDA

AD0

3.3V

5V

P11

P12

P13

P14

P15

SCL

SCL

BLINK

I/O

RST

I/O

P9

OUTPUT

OUTPUT

GND

5V

INPUT 1

INPUT 2

INPUT 3

INPUT 4

INPUT 5

0.047

µF

INT

INT/O16

Typical Application Circuit

19-3170; Rev 4; 4/05

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.

Ordering Information

PART

TEMP RANGE

PIN-

PACKAGE

PKG

CODE

MAX7314ATG

-40

°C to +125°C

24 Thin QFN

4mm x 4mm

x 0.8mm

T2444-4

MAX7314AEG

-40

°C to +125°C 24 QSOP

—

Pin Configurations continued at end of data sheet.

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