Driving Load Currents Higher than 20mA

The MAX7323 can be used to drive loads, such as

relays, that draw more than 20mA by paralleling out-

puts. Use at least one output per 20mA of load current;

for example, a 5V, 330mW relay draws 66mA, and

therefore, requires four paralleled outputs. Any combi-

nation of outputs can be used as part of a load-sharing

design because any combination of ports can be set or

cleared at the same time by writing to the MAX7323. Do

not exceed a total sink current of 100mA for the device.

The MAX7323 must be protected from the negative volt-

age transient generated when switching off inductive

loads (such as relays), by connecting a reverse-biased

diode across the inductive load. Choose the peak cur-

rent for the diode to be greater than the inductive load’s

operating current.

Power-Supply Considerations

The MAX7323 operates with a supply voltage of +1.71V

to +5.5V over the -40°C to +125°C temperature range.

Bypass the supply to GND with a ceramic capacitor of

at least 0.047µF as close as possible to the device. For

the TQFN version, additionally connect the exposed

paddle to GND.

and 4 Open-Drain I/Os

14

______________________________________________________________________________________

15

16

14

13

5

6

7

8

13

V+

4

12

10

9

AD0

RST

P5

P4

GND

P3

MAX7323

2

11

SDA

TQFN

TOP VIEW

*EP

*EXPOSED PADDLE, CONNECTED TO GND

+

+

Pin Configurations

16

15

14

13

12

11

10

9

1

2

3

4

5

6

7

8

AD0

V+

SDA

SCL

INT

O7

O6

P5

P4

MAX7323

QSOP

RST

AD2

P2

O0

O1

P3

GND

+

+