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LTC1518/LTC1519
52Mbps Precision Delay
RS485 Quad Line Receivers
s
Precision Propagation Delay: 18.5ns
±3.5ns Over
0
°C to 70°C Temperature Range
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High Data Rate:
52Mbps
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Low tPLH/tPHL Skew: 500ps Typ
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Low Channel-to-Channel Skew: 500ps Typ
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Guaranteed Fail-Safe Operation over the Entire
Common Mode Range
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–7V to 12V RS485 Input Common Mode Range
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Input Resistance
≥22k, Even When Unpowered
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Hot Swap
TM Capable
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High Common Mode Rejection to 26MHz
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Short-Circuit Protection: 10mA Typ Output Current
for an Indefinite Short
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Three-State Output Capability
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Will Not Oscillate with Slow Moving Input Signals
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Single 5V Supply
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Pin Compatible with LTC488, LTC489
The LTC
1518/LTC1519 are high speed, precision delay
differential quad bus/line receivers that can operate at data
rates as high as 52Mbps. They are pin compatible with the
LTC488/LTC489 RS485 line receivers and operate over the
entire – 7V to 12V common mode range. A unique architec-
ture provides very stable propagation delays and low skew
over wide input common mode, input overdrive and ambi-
ent temperature ranges. Propagation delay is 18.5ns
±3.5ns
over the commercial temperature range. Typical tPLH/tPHL
and channel-to-channel skew is 500ps.
Each receiver translates differential input levels (
VID ≥
300mV) into valid CMOS and TTL output levels. Its high
input resistance (
≥22k) allows many receivers to be con-
nected to the same driver. The receiver outputs go into a
high impedance state when disabled.
The receivers have a fail-safe feature that guarantees a high
output state when the inputs are shorted or left floating.
Other protection features include thermal shutdown and a
controlled maximum short-circuit current (50mA Max).
Input resistance remains
≥22k when the device is
unpowered or disabled, thus allowing hot swapping with-
out loading the data lines.
The LTC1518/LTC1519 operate from a single 5V supply
and draw 12mA of supply current.
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High Speed RS485/RS422 Receivers
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STS-1/OC-1 Data Receivers
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PECL Line Receivers
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Level Translators
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Fast-20/Fast-40 SCSI Receiver
Propagation Delay Guaranteed to Fall
Within Shaded Area (
±3.5ns)
52Mbps Data Communication over Twisted Pair
, LTC and LT are registered trademarks of Linear Technology Corporation.
Hot Swap is a trademark of Linear Technology Corporation.
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
1518/19 TA02
VIN =
3V/DIV
VOUT =
5V/DIV
–5
5
15
TIME (ns)
25
35
0
10203040 45
RECEIVER
INPUT
VID = 1.5V
RECEIVER
OUTPUT
VDD = 5V
TA = 0°C TO 70°C
100
A 1
4
EN
RO
1518/19 F08
1/4 LTC1518
LTC1685
12
3
2 B
7
6
3
2
DE
DI
RO
4
1
100
7
6
3
2
DE
DI
RO
4
1
RE