Datasheet

4
LTC1334
AC ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the
safety of the device cannot be guaranteed.
Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to device ground unless
otherwise specified.
Note 3: All typicals are given at V
CC
= 5V, C1 = C2 = C3 = C4 = 0.1µF
and T
A
= 25°C.
Note 4: Short-circuit current for RS485 driver output low state folds back
above V
CC
. Peak current occurs around V
O
= 3V.
Note 5: The “B” RS232 receiver output is disabled in RS485 mode
(SEL1 = SEL2 = high). The unused output driver goes into a high
impedance mode and has a resistor to V
CC
. See Applications Information
section for more details.
TYPICAL PERFORMANCE CHARACTERISTICS
U
W
Receiver Output High Voltage
vs Temperature
TEMPERATURE (°C)
–50
OUTPUT VOLTAGE (V)
5.0
4.9
4.8
4.7
4.6
4.5
4.4
4.3
4.2
4.1
4.0
0
50
75
LTC1334 • TPC01
–25
25
100
125
I
OUT
= 3mA
V
CC
= 5V
TEMPERATURE (°C)
–50
TIME (ns)
20
18
16
14
12
10
8
6
4
2
0
0
50
75
LTC1334 • TPC03
–25
25
100
125
V
CC
= 5V
RS485 Receiver Skew
t
PLH
– t
PHL
vs Temperature
TEMPERATURE (°C)
–50
OUTPUT VOLTAGE (V)
0.5
0.4
0.3
0.2
0.1
0
0
50
75
LTC1334 • TPC02
–25
25
100
125
I
OUT
= 3mA
V
CC
= 5V
Receiver Output Low Voltage
vs Temperature
The denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V, C1 = C2 = C3 = C4 = 0.1µF (Notes 2, 3)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
RS485 Mode (SEL1 = SEL2 = High)
t
ZL
Driver Enable to Output Low Figures 3, 7, C
L
= 100pF, S1 Closed 50 90 ns
t
ZH
Driver Enable to Output High Figures 3, 7, C
L
= 100pF, S2 Closed 50 90 ns
t
LZ
Driver Disable from Low Figures 3, 7, C
L
= 15pF, S1 Closed 50 90 ns
t
HZ
Driver Disable from High Figures 3, 7, C
L
= 15pF, S2 Closed 60 90 ns
t
PLH
Receiver Input to Output Figures 2, 8, R
L
= 54, C
L
= 100pF 20 60 140 ns
t
PHL
Receiver Input to Output Figures 2, 8, R
L
= 54, C
L
= 100pF 20 70 140 ns
t
SKEW
Differential Receiver Skew, t
PLH
– t
PHL
Figures 2, 8, R
L
= 54, C
L
= 100pF 10 ns