LTC1386
PI FU CTIO S
VCC: 3.3V Input Supply Pin. This pin should be decoupled
with a 0.1µF ceramic capacitor.
GND: Ground Pin.
V+: Positive Supply Output (EIA/TIA562 Drivers). V+ ≅
2VCC – 1V. This pin requires an external capacitor C =
0.1µF for charge storage. The capacitor may be tied to
ground or VCC. With multiple devices, the V + and V – pins
may share a common capacitor. For large numbers of
devices, increasing the size of the shared common storage
capacitors is recommended to reduce ripple.
V–: Negative Supply Output (RS232 Drivers). V – ≅ – (2VCC
– 1.3V). This pin requires an external capacitor C = 0.1µF
for charge storage.
C1+, C1–, C2+, C2–: Commutating Capacitor Inputs. These
pins require two external capacitors C = 0.1µF: one from
C1+ to C1– and another from C2+ to C2 –. To maintain
charge pump efficiency, the capacitor’s effective series
resistance should be less than 2Ω.
TR IN: EIA/TIA562 Driver Input Pins. Inputs are TTL/
CMOS compatible. The inputs of unused drivers can be left
unconnected since 300k input pull-up resistors to VCC are
included on chip.
TR OUT: Driver Outputs at EIA/TIA562 Voltage Levels.
The driver 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
Levels.
UW
W
SWITCHI G TI E WAVEFOR S
DRIVER
INPUT
1.4V
DRIVER
OUTPUT
0V
tLHD
1.4V
tHLD
VCC
0V
V+
0V
V–
LTC1386 • F01
Figure 1. Driver Propagation Delay Timing
4
RX
1.7V
INPUT
RX
OUTPUT
0.8V
tLHR
VCC
1.3V
0V
tHLR
2.4V VCC
0V
LTC1386 • F02
Figure 2. Receiver Propagation Delay Timing
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