
Rev:B Date: 02/26/04
SP1481E Low Power Half-Duplex RS485 Transceivers
2
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
............................................................................................................+7V
Input Voltages
Logic........................................................-0.3V to (V
CC
+0.5V)
Drivers..................................................-0.3V to (V
+0.5V)
Receivers.................................................................
±
15V
T
MIN
to T
MAX
and V
CC
= 5V
±
5% unless otherwise noted.
PARAMETERS
SP1481E DRIVER
DC Characteristics
Differential Output Voltage
Differential Output Voltage
MIN.
TYP.
MAX.
UNITS
CONDITIONS
3.5
2
V
CC
V
CC
Volts
Volts
Unloaded; R =
∞
; see Figure 1
with load; R = 50
; (RS-422);
see Figure 1
with load; R = 27
; (RS-485);see Figure 1
Differential Output Voltage
Change in Magnitude of Driver
Differential Output Voltage for
Complimentary States
Driver Common-Mode
Output Voltage
Input High Voltage
Input Low Voltage
Input Current
Driver Short-Circuit Current
V
OUT
= HIGH
V
OUT
= LOW
SP1481E DRIVER
AC Characteristics
Maximum Data Rate
1.5
V
CC
Volts
0.2
Volts
R = 27
or R = 50
; see Figure 1
3
Volts
Volts
Volts
μ
A
R = 27
or R = 50
; see Figure 1
Applies to DE, DI, RE
Applies to DE, DI, RE
Applies to DE, DI, RE
2.0
0.8
±
10
±
250
±
250
mA
mA
-7V
≤
V
O
≤
+12V
-7V
≤
V
O
≤
+12V
20
Mbps
RE = 5V, DE = 5V; R
DIFF
= 54
,
C
L1
= C
L2
= 100pF
t
; R
= 54
, C
= C
L2
= 100pF;
see Figures 3 and 5
Driver Input to Output
10
30
40
ns
10
ns t
PHL
; R
DIFF
= 54
, C
LI
= C
L2
= 100pF;
Driver Skew
3
ns
see Figures 3 and 5,
t
= | t
- t
|
From 10% to 90%; R
= 54
,
C
L1
= C
= 100pF; s
ee Figures 3 &
6
C
= 100pF; see Figures 4 & 6;S
2
closed
70
ns
C
= 100pF; see Figures 4 & 6;S
1
closed
70
ns
C
= 100pF; see Figures 4 & 6;S
1
closed
70
ns
C
= 100pF; see Figures 4 & 6;S
2
closed
Driver Rise or Fall Time
8
20
ns
Driver Enable to Output High
40
70
ns
Driver Enable to Output Low
40
Driver Disable Time from Low
40
Driver Disable Time from High
40
Output Voltages
Logic........................................................-0.3V to (V
+0.5V)
Drivers......................................................................
15V
Receivers............................................-0.3V to (V
+0.5V)
Storage Temperature.......................................................-65C to +150C
Power Dissipation per Package
8-pin NSOIC (derate 6.60mW/
o
C above +70
o
C)...........................550mW
8-pin PDIP (derate 11.8mW/
o
C above +70
o
C)............................1000mW
ELECTRICAL CHARACTERISTICS