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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510)668-7017 • www.exar.com SP490,491_101_062711
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 specications below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect reliability.
V
CC
....................................................................................................+7V
Input Voltages
Drivers................................................-0.5V to (V
CC
+0.5V)
Receivers..................................................................±14V
Output Voltages
Drivers......................................................................±14V
Receivers...........................................-0.5V to (V
CC
+0.5V)
Storage Temperature....................................................-65˚C to +150˚
Power Dissipation.....................................................................1000mW
PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
SP490 DRIVER
DC Characteristics
Differential Output Voltage GND V
CC
Volts Unloaded; R = ∞ ; see gure 1
Differential Output Voltage 2 V
CC
Volts With Load; R = 50Ω; (RS422);
see gure 1
Differential Output Voltage 1.5 V
CC
Volts With Load; R = 27Ω; (RS485); see
gure 1
Change in Magnitude of Driver
Differential Output Voltage for
Complimentary States 0.2 Volts R = 27Ω or R = 50Ω; see gure 1
Driver Common-Mode
Output Voltage 3 Volts R = 27Ω or R = 50Ω; see gure 1
Input High Voltage 2.0 Volts Applies to D
Input Low Voltage 0.8 Volts Applies to D
Input Current ±10 µA Applies to D
Driver Short-Circuit Current
V
OUT
= HIGH 250 mA -7V ≤ V
O
≤ +12V
V
OUT
= LOW 250 mA -7V ≤ V
O
≤ +12V
SP490 DRIVER
AC Characteristics
Maximum Data Rate 5 Mbps
Driver Input to Output 30 60 ns t
PLH
; R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF;
see gures 3 and 6
Driver Input to Output 30 60 ns t
PHL
; R
DIFF
= 54Ω, C
L1
= C
L2
= 100pF;
see gures 3 and 6
Driver Skew 5 ns see gures 3 and 6,
t
SKEW
= | t
DPLH
- t
DPHL
|
Driver Rise or Fall Time 15 40 ns From 10% to 90%; R
DIFF
= 54Ω,
C
L1
= C
L2
= 100pF; see gures 3 and 6
SP490 RECEIVER
DC Characteristics
Differential Input Threshold -0.2 +0.2 Volts -7V ≤ V
CM
≤ 12V
Input Hysteresis 70 mV V
CM
= 0V
Output Voltage High 3.5 Volts I
O
= -4mA, V
ID
= +200mV
Output Voltage Low 0.4 Volts I
O
= +4mA, V
ID
= -200mV
Input Resistance 12 15 kΩ -7V ≤ V
CM
≤ 12V
Input Current (A, B); V
IN
= 12V ±1.0 mA V
IN
= 12V
Input Current (A, B); V
IN
= -7V -0.8 mA V
IN
= -7V
Short-Circuit Current 85 mA 0V ≤ V
O
≤ V
CC
ELECTRICAL CHARACTERISTICS
T
MIN
to T
MAX
and V
CC
= 5V ± 5% unless otherwise noted.
