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 second sources to the PCF8574 and

PCF8574A.

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 MAX7320 is a general-purpose port expander

operating from a +1.71V to +5.5V supply that provides

eight push-pull output ports. The MAX7320 is rated to

sink a total of 100mA and source a total of 50mA from

all eight combined outputs.

(0x50 to 0x5F) using address select inputs AD0 and AD2,

slave addresses than the MAX7319, MAX7321,

MAX7322, and MAX7323 (these expanders use the

address range 0x60 to 0x6F).

_______________________________________________________________________________________

5

PART

SLAVE

ADDRESS

INPUTS

INPUT

INTERRUPT

MASK

OPEN-

DRAIN

OUTPUTS

PUSH-

PULL

OUTPUTS

APPLICATION

8-PORT EXPANDERS

MAX7319

110xxxx

8

Yes

—

—

Input-only versions:

Eight input ports with programmable latching

transition detection interrupt and selectable pullups.

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.

MAX7320

101xxxx

—

—

—

8

Output-only versions:

Eight push-pull outputs with selectable power-up

default states.

Push-pull outputs offer faster rise time than open-

drain outputs, and require no pullup resistors.

MAX7321

110xxxx

Up to 8

—

Up to 8

—

I/O versions:

Eight open-drain I/O ports with latching transition

detection interrupt and selectable pullups.

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.

MAX7322

110xxxx

4

Yes

—

4

Four input-only, four output-only versions:

Four input ports with programmable latching

transition detection interrupt and selectable pullups.

Four push-pull outputs with selectable power-up

default levels.

Table 1. MAX7319–MAX7329 Family Comparison