LTC485I LINER [Linear Technology], LTC485I Datasheet - Page 3

• Manufacturer Part Number: LTC485I
• Description: Low Power RS485 Interface Transceiver
• Manufacturer: LINER [Linear Technology]

SWITCHI G CHARACTERISTICS
TEST CIRCUITS
SYMBOL
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
The
temperature range.
Note 1: Absolute maximum ratings are those beyond which the safety of
the device cannot be guaranteed.
Note 2: All currents into device pins are positive; all currents out ot device
pins are negative. All voltages are referenced to device ground unless
otherwise specified.
PLH
PHL
SKEW
r
ZH
ZL
LZ
HZ
PLH
PHL
SKD
ZL
ZH
LZ
HZ
, t
f
DI
denotes specifications which apply over the full operating
3V
Figure 3. Driver/Receiver Timing Test Circuit
DE
PARAMETER
Driver Input to Output
Driver Input to Output
Driver Output to Output
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
Receiver Input to Output
Receiver Enable to Output Low
Receiver Enable to Output High
Receiver Disable from Low
Receiver Disable from High
t
PLH
A
B
U
– t
Figure 1. Driver DC Test Load
PHL
A
B
R
Differential Receiver Skew
DIFF
V
OD
LTC485 • F01
R
R
C
C
L1
L2
V
A
B
OC
RE
15pF
CONDITIONS
R
(Figures 3 and 5)
C
C
C
C
R
(Figures 3 and 7)
C
C
C
C
LTC485 • F03
L
L
L
L
RL
RL
RL
RL
DIFF
DIFF
RO
= 100pF (Figures 4 and 6) S2 Closed
= 100pF (Figures 4 and 6) S1 Closed
= 15pF (Figures 4 and 6) S1 Closed
= 15pF (Figures 4 and 6) S2 Closed
= 15pF (Figures 2 and 8) S1 Closed
= 15pF (Figures 2 and 8) S2 Closed
= 15pF (Figures 2 and 8) S1 Closed
= 15pF (Figures 2 and 8) S2 Closed
V
= 54 , C
= 54 , C
CC
= 5V 5%, unless otherwise noted. (Notes 2 and 3)
L1
L1
Note 3: All typicals are given for V
Note 4: The LTC485 is guaranteed by design to be functional over a supply
voltage range of 5V 10%. Data sheet parameters are guaranteed over the
tested supply voltage range of 5V 5%.
= C
= C
L2
L2
= 100pF,
= 100pF,
RECEIVER
UNDER TEST
OUTPUT
OUTPUT
Figure 4. Driver Timing Test Load #2
Figure 2. Receiver Timing Test Load
TEST POINT
C
15pF
RL
C
500
L
MIN
10
10
30
30
CC
3
= 5V and T
1k
S1
S2
TYP
30
30
15
40
40
40
40
90
90
13
20
20
20
20
5
A
S1
S2
= 25 C.
1k
LTC485 • F02
LTC485
MAX
LTC485 • F02
200
200
V
50
50
10
25
70
70
70
70
50
50
50
50
CC
V
CC
UNITS
3
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns