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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com SP3485_100_061912
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
.....................................................................+6.0V
Input Voltages
Logic....................................-0.3V to +6.0V
Drivers.................................-0.3V to +6.0V
Receivers.........................................+/-15V
Output Voltages
Drivers.............................................+/-15V
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)
ELECTRICAL CHARACTERISTICS
T
AMB
= T
MIN
to T
MAX
and V
CC
= +3.3V +/-5% unless otherwise noted.
PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS
SP3485 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 1
Differential Output Voltage 1.5 Vcc Volts With Load; R = 27Ω (RS-485);
Figure 1
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 Applies to DE, DI, RE
Input Low Voltage 0.8 Volts Applies to DE, DI, RE
Input Current +/-10 µA Applies to DE, DI, RE
Driver Short Circuit Current
V
OUT
= HIGH
+/-250 mA -7V ≤ V
O
≤ +12V; Figure 8
Driver Short Circuit Current
V
OUT
= LOW
+/-250 mA -7V ≤ V
O
≤ +12V; Figure 8
SP3485 DRIVER
AC Characteristics
Maximum Data Rate 10 Mbps RE = V
CC
, DE = V
CC
Driver Input to Output, t
PLH
20 40 60 ns Figures 2 & 9
Driver Input to Output, t
PHL
20 40 60 ns Figures 2 & 9
Differential Driver Skew 2 10 ns |t
DO1
- t
DO2
|, Figures 2 and 10
Driver Rise or Fall Time 5 20 ns From 10%-90%; Figures 3 and 10
