LTC1385 Linear Technology, LTC1385 Datasheet - Page 5

• Manufacturer Part Number: LTC1385
• Description: 3.3V Low Power EIA/TIA-562 Transceiver
• Manufacturer: Linear Technology

PI FU CTIO S
V
with a 0.1 F ceramic capacitor.
GND: Ground Pin.
ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic
low puts the device in the Shutdown mode independent
of the Driver Disable pin. The supply current drops to
0.2 A and all driver and receiver outputs are forced into
three-state.
DRIVER DISABLE: TTL/CMOS Compatible Input Pin. With
the ON/OFF pin held high, a logic low forces the part into
the Driver Disable mode with the charge pump turned off
and the driver outputs forced into three-state. Both receiv-
ers remain active and the supply current drops to 35 A. A
logic high forces the part into the Normal mode.
V
V
C = 0.1 F for charge storage. The capacitor may be tied
to ground or V
pins may share a common capacitor. For a large number
of devices, increasing the size of the shared common
storage capacitors is recommended to reduce ripple.
V
V
capacitor C = 0.1 F for charge storage.
OUTPUT
SWITCHI G TI E WAVEFOR S
DRIVER
DRIVER
INPUT
CC
+
+
–
–
: Positive Supply Output (EIA/TIA-562 Drivers).
: Negative Supply Output (EIA/TIA-562 Drivers).
U
: 3.3V Input Supply Pin. This pin should be decoupled
2V
– (2V
CC
t
LHD
Figure 1. Driver Propagation Delay Timing
U
1.4V
– 1V. This pin requires an external capacitor
CC
U
CC
– 1.3V). This pin requires an external
. With multiple devices, the V
0V
U
W
1.4V
t
HLD
W
+
and V
0V
1385 F01
V
0V
V
V
CC
+
–
–
OUTPUT
C1
pins require two external capacitors C = 0.1 F: one from
C1
charge pump efficiency, the capacitor’s effective series
resistance should be less than 2 .
TR IN: EIA/TIA-562 Driver Input Pins. Inputs are TTL/
CMOS compatible. The inputs of unused drivers can be left
unconnected since 300k input pull-up resistors to V
included on chip. To minimize power consumption, the
internal driver pull-up resistors are disconnected from V
in the Shutdown mode.
TR OUT: Driver Outputs at EIA/TIA-562 Voltage Levels.
Outputs are in a high impedance state when in the Shut-
down or Driver Disable mode or V
outputs are protected against ESD to 10kV for human
body model discharges.
RX IN: Receiver Inputs. These pins can be forced to 25V
without damage. The receiver inputs are protected against
ESD to 10kV for human body model discharges. Each
receiver provides 0.4V of hysteresis for noise immunity.
RX OUT: Receiver Outputs with TTL/CMOS Voltage Lev-
els. Outputs are in a high impedance state when in the
Shutdown mode.
INPUT
+
+
RX
RX
, C1
to C1
t
–
LHR
Figure 2. Receiver Propagation Delay Timing
, C2
–
, and another from C2
+
, C2
1.7V
0.8V
–
: Commutating Capacitor Inputs. These
+
to C2
CC
1.3V
= 0V. The driver
LTC1385
–
. To maintain
t
HLR
2.4V
CC
1385 F02
5
are
V
0V
V
0V
CC
CC
CC