Human Body Model (HBM).......................................... ±2kV
Electrical Characteristics
Unless otherwise noted: T
AMB
= T
MIN
to T
MAX
and V
CC
= 3.3V ±5%.
PARAMETERS
SP3485 Driver DC Characteristics
Differential output voltage
Differential output voltage
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
Driver short circuit current V
OUT
= LOW
SP3485 Driver AC Characteristics
Maximum data rate
Driver input to output, t
PLH
Driver input to output, t
PHL
Differential driver skew
Driver rise or fall time
Driver enable to output high
Driver enable to output low
Driver disable time from low
Driver disable time from high
Driver enable from shutdown to output high, t
PSH
Driver enable from shutdown to output low, t
PSL
Time to shutdown, t
SHDN
50
200
REV 2.0.1
MIN.
TYP.
MAX.
Vcc
UNITS
Volts
Volts
Volts
Volts
Volts
Volts
Volts
µA
mA
mA
Mbps
CONDITIONS
Unloaded; R = ∞Ω ; Figure 1
With Load; R = 50Ω (RS-422); Figure 1
With Load; R = 27Ω (RS-485); Figure 1
R = 27Ω or R = 50Ω; Figure 1
R = 27Ω or R = 50Ω; Figure 1
Applies to DE, DI, RE
Applies to DE, DI, RE
Applies to DE, DI, RE
-7V ≤ V
O
≤ +12V; Figure 8
-7V ≤ V
O
≤ +12V; Figure 8
RE = V
CC
, DE = V
CC
Figures 2 & 9
Figures 2 & 9
2
1.5
Vcc
Vcc
0.2
3
2.0
0.8
±10
±250
±250
10
17
17
2
5
35
30
20
20
60
60
10
20
120
120
120
120
250
250
600
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
|
t
DO1
- t
DO2
|
, Figures 2 and 10
From 10%-90%; Figures 3 and 10
Figures 4 and 11
Figures 5 and 11
Figures 5 and 11
Figures 4 and 11
C
L
= 50pF, R
L
= 500Ω.
Figures 4, 5, and 11
Notes 1 and 2
2/9
SP3485
Electrical Characteristics (Continued)
Unless otherwise noted: T
AMB
= T
MIN
to T
MAX
and V
CC
= 3.3V ±5%.
PARAMETERS
SP3485 Receiver DC Characteristics
Differential input threshold
Input hysteresis
Output voltage HIGH
Output voltage LOW
Three-state (high impedance) output current
Input resistance
Input current (A, B); V
IN
= 12V
Input current (A, B); V
IN
= -7V
Short circuit current
SP3485 Receiver AC Characteristics
Maximum data rate
Receiver input to output, t
PLH
Receiver input to output, t
PLH
Receiver input to output, t
PHL
Receiver input to output, t
PHL
Differential receiver skew
Receiver enable to output low
Receiver enable to output high
Receiver disable from low
Receiver disable from high
Receiver enable from shutdown to output high,
t
PRSH
Receiver enable from shutdown to output low, t
PRSL
Time to shutdown, t
SHDN
Power Requirements
Supply current , no load
Supply current , no load
425
300
2000
1500
µA
µA
RE, DI = 0V or V
CC
; DE = V
CC
RE = 0V, DI = 0V or V
CC
, DE = 0V
50
200
4
10
10
10
10
60
60
60
60
1800
1800
600
35
10
40
100
70
100
70
Mbps
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
RE = 0V, DE = 0V
Figures 6 and 12
T
AMB
= 25°C, Vcc = 3.3V,
Figures 6 and 12
Figures 6 and 12
T
AMB
= 25°C, Vcc = 3.3V,
Figures 6 and 12
t
RSKEW
= t
RPHL
- t
RPLH
,
Figures 6 and 12
Figures 7 and 13,
S
1
closed, S
2
open
Figures 7 and 13,
S
2
closed, S
1
open
Figures 7 and 13,
S
1
closed, S
2
open
Figures 7 and 13,
S
2
closed, S
1
open
C
L
= 15pF, R
L
= 1kΩ.
Figures 7 and 13
Notes 1 and 2
7
12
1.0
-0.8
60
Vcc-0.4
0.4
±1
-0.2
20
0.2
Volts
mV
Volts
Volts
µA
kΩ
mA
mA
mA
-7V ≤ V
CM
≤ 12V
V
CM
= 0V
V
ID
= 200mV, -1.5mA
V
ID
= -200mV, 2.5mA
0V ≤ V
O
≤ V
CC
; RE = V
CC
-7V ≤ V
CM
≤ 12V
DE = 0V, V
CC
= 0V or 3.6V,
V
IN
= 12V
DE = 0V, V
CC
= 0V or 3.6V,
V
IN
= -7V
0V ≤ V
CM
≤ V
CC
MIN.
TYP.
MAX.
UNITS
CONDITIONS
|
|
NOTES:
1. The transceivers are put into shutdown by gringing RE high and DE low simultaneously for at least 600ns. If the control inputs are in this state for less than 50ns, the
device is guaranteed to not enter shutdown. If the enable inputs are held in this state for at least 600ns, the device is assured to be in shutdown. Note that the receiver
and driver times increase significantly when coming out of shutdown.
2. This spec is guaranteed by design and bench characterization.
REV 2.0.1
3/9
SP3485
Pin Functions
Pin
1
2
3
4
5
6
7
8
Name
RO
RE
DE
DI
GND
A
B
V
CC
Description
Receiver output
Receiver output enable active LOW
Driver output enable active HIGH
Driver input
Ground connection
Non-inverting driver output / receiver input
Inverting driver output / receiver input
Positive supply
RO 1
RE 2
DE 3
DI 4
D
R
8 V
CC
7 B
6 A
5 GND
SP3485
Pinout (Top View)
REV 2.0.1
4/9
SP3485
Test Circuits
R
D
Vcc
V
OD
R
V
OC
D
GENERATOR
(NOTE 1)
50Ω
C
L
15pF
(NOTE 2)
R
L
OUT
54Ω
V
CC
Figure 1: Driver DC Test Load Circuit
Figure 2: Driver Propagation Delay Test Circuit
S1
D
OUT
C
L
= 50pF
(NOTE 2)
GENERATOR
(NOTE 1)
50Ω
R
L
= 110Ω
C
L
D
GENERATOR
(NOTE 1)
50Ω
R
L
=
OUT
60Ω
V
CC
C
L
= 15pF (NOTE 2)
Figure 3: Driver Differential Output Delay
and Transition Time Circuit.
V
CC
R
L
= 110Ω
OUT
C
L
= 50pF
(NOTE 2)
GENERATOR
(NOTE 1)
50Ω
Figure 4: Driver Enable and Disable Timing Circuit,
Output High
S1
0V OR 3V
D
V
ID
GENERATOR
(NOTE 1)
R
OUT
C
L
= 15pF
(NOTE 2)
50Ω
1.5V
0V
Figure 5: Driver Enable and Disable Timing Circuit,
Output Low
S3
1k
V
ID
R
S2
C
L
= 15pF
(NOTE 2)
GENERATOR
(NOTE 1)
Figure 6: Receiver Propagation Delay Test Circuit
1.5V
-1.5V
S1
V
CC
DE = 0 or Vcc
DI = 0 or Vcc
D
A
I
OSD
B
-7V to +12V V
50Ω
Figure 7: Receiver Enable and Disable Timing Circuit
NOTES
1: The input pulse is supplied by a generator with the following characteristics:
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