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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com

SP3490_349_02_0270

ABSOLUTE MAXIMUM RATINGS

These are stress ratings only and functional operation

of the device at these ratings or any other above those

indicated in the operation sections of the specifications

below is not implied. Exposure to absolute maximum

rating conditions for extended periods of time may

affect reliability.

V

Input Voltages

Logic....................................-0.3V to +6.0V

Drivers.................................-0.3V to +6.0V

Receivers.........................................+/-4V

Output Voltages

Drivers.............................................+/-4V

Receivers............................-0.3V to +6.0V

Storage Temperature.......................-65˚C to +150˚C

Power Dissipation

8-pin NSOIC...................................................600mW

(derate 6.90mW/ºC above +70ºC)

4-pin NSOIC.................................................700mW

(derate 8.33mW/ºC above +70ºC)

ELECTRICAL CHARACTERISTICS

T

PARAMETERS

MIN.

TYP.

MAX.

UNITS CONDITIONS

SP3490 DRIVER

DC Characteristics

Differential Output Voltage

GND

Vcc

Volts

Unloaded; R = ∞Ω ; Figure 1

Differential Output Voltage

2

Vcc

Volts

With Load; R = 50Ω (RS-422);

Figure 

Differential Output Voltage

.5

Vcc

Volts

With Load; R = 27Ω (RS-485);

Figure 

Change in Magnitude of Driver

Differential Output Voltage for

Complimentary states

0.2

Volts

R = 27Ω or R = 50Ω; Figure 1

Driver Common Mode Output

Voltage

3

Volts

R = 27Ω or R = 50Ω; Figure 1

Input High Voltage

2.0

Volts

Input Low Voltage

0.8

Volts

Input Current

+/-0

µA

Driver Short Circuit Current

V

+/-250

mA

-7V ≤ V

V

+/-250

mA

-7V ≤ V

SP3490 DRIVER

AC Characteristics

Max. Transmission Rate

0

Mbps

Driver Input to Output, t

PLH

20

40

60

ns

R = 27Ω, Figures 2 & 9

Driver Input to Output, t

PHL

20

40

60

ns

R = 27Ω, Figures 2 & 9

Differential Driver Skew

2

ns

|t

Figures 2 and 9

Driver Rise or Fall Time

5

20

ns

From 0%-90%; Figures 3 and 0