9

FN6073.3

±15kV HBM. The RS-485 pins are particularly vulnerable to

ESD damage because they typically connect to an exposed

port on the exterior of the finished product. Simply touching

the port pins, or connecting a cable, can cause an ESD

event that might destroy unprotected ICs. These new ESD

structures protect the device whether or not it is powered up,

protect without allowing any latch-up mechanism to activate,

and without degrading the RS-485 common mode range of

-7V to +12V. This built-in ESD protection eliminates the need

for board level protection structures (e.g., transient

suppression diodes), and the associated, undesirable

capacitive load they present.

FIGURE 6. DRIVER OUTPUT CURRENT vs DIFFERENTIAL

OUTPUT VOLTAGE

FIGURE 7. DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs

TEMPERATURE

FIGURE 8. DRIVER OUTPUT CURRENT vs SHORT CIRCUIT

VOLTAGE

FIGURE 9. SUPPLY CURRENT vs TEMPERATURE

DIFFERENTIAL OUTPUT VOLTAGE (V)

01

2345

0

10

20

30

40

50

60

70

80

90

-40

0

50

85

2

2.2

2.4

2.6

2.8

3

3.2

3.4

3.6

TEMPERATURE (°C)

-25

25

75

OUTPUT VOLTAGE (V)

-7 -6

-4

-2

0

2

4

6

8

10

12

-60

-40

-20

0

20

40

60

80

100

120

140

160

-80

-100

-120

Y OR Z = HIGH

Y OR Z = LOW

ISL8491E

ISL8491E

ISL8488E/89E

ISL8488E/89E

-40

0

50

85

TEMPERATURE (°C)

-25

25

75

50

100

150

200

250

300

350

400

ISL8491E, DE = X, RE = X

ISL8489E, DE = X, RE = X

ISL8488E

ISL8488E, ISL8489E, ISL8491E