4

Receiver Short-Circuit Current

0V

Full

7

-

85

mA

SWITCHING CHARACTERISTICS

Driver Input to Output Prop Delay

Full

2

9

15

ns

Driver Prop Delay Skew

Full

-

1

5

ns

Driver Differential Rise or Fall Time

Full

-

5

15

ns

Driver Enable to Output High

Full

-

9

25

ns

Driver Enable to Output Low

Full

-

9

25

ns

Matched Enable Switching

(Figure 3)

Full

-

1

3

ns

Driver Disable from Output High

Full

-

9

25

ns

Driver Disable from Output Low

Full

-

9

25

ns

Matched Disable Switching

∆t

DIS

(Figure 3)

Full

-

2

5

ns

Driver Maximum Data Rate

Full

30

-

-

Mbps

Receiver Input to Output Prop

Delay

Full

8

17

30

ns

Receiver Prop Delay Skew

(Figure 5)

Full

-

1

5

ns

Receiver Enable to Output High

Full

-

7

20

ns

Receiver Enable to Output Low

Full

-

7

20

ns

Receiver Disable from Output High

Full

-

7

20

ns

Receiver Disable from Output Low

Full

-

7

20

ns

Receiver Maximum Data Rate

Full

30

-

-

Mbps

NOTES:

2. All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to device ground unless

otherwise specified.

3. Supply current specification is valid for loaded drivers when DE = 0V.

4. Applies to peak current. See “Typical Performance Curves” for more information.

5. Devices meeting these limits are denoted as “1 unit load (UL)” transceivers. The RS-485 standard allows up to 32 Unit Loads on the bus, so a

1UL transceiver permits > 32 devices on the bus.

Test Circuits and Waveforms

FIGURE 1. DC DRIVER TEST CIRCUITS

Electrical Specifications

Note 2 (Continued)

PARAMETER

SYMBOL

TEST CONDITIONS

TEMP

MIN

TYP

MAX

UNITS

D

DE

DI

R

R

Z

Y

D

DE

DI

375

Ω

375

Ω

Z

Y

-7V to +12V

ISL81485