LT1180A/LT1181A
TYPICAL PERFOR A CE CHARACTERISTICS
Receiver Short-Circuit Current
50
SHORT-CIRCUIT CURRENT (mA)
40
SLEW RATE (V/µs)
30
RX I
SC
20
10
0
–55 –25
50
25
0
75
TEMPERATURE (°C)
Shutdown to Driver Outputs
10V
DRIVER 1
OUTPUT
5V
GND
GND
DRIVER 2
OUTPUT
– 5V
– 10V
DRIVER OUTPUT
R
L
= 3k
DRIVER OUTPUT
R
L
= 3k
C
L
= 2500pF
ON/OFF PIN
INPUT
LT1180A • TPC12
LT1180A • TPC13
PI FU CTIO S
V
CC
:
5V Input Supply Pin. This pin should be decoupled
with a 0.1µF ceramic capacitor close to the package pin.
Insufficient supply bypassing can result in low output
drive levels and erratic charge pump operation.
GND:
Ground Pin.
ON/OFF:
A TTL/CMOS Compatible Operating Mode Con-
trol. A logic low puts the LT1180A in shutdown mode.
Supply current drops to zero and both driver and receiver
outputs assume a high impedance state. A logic high fully
enables the device.
V
+
:
Positive Supply Output (RS232 Drivers). V
+
≈
2V
CC
–
1.5V. This pin requires an external charge storage capaci-
tor C
≥
0.1µF, tied to ground or V
CC
. Larger value capaci-
tors may be used to reduce supply ripple. With multiple
transceivers, the V
+
and V
–
pins may be paralleled into
common capacitors.
V
–
:
Negative Supply Output (RS232 Drivers). V
–
≈
–(2V
CC
– 2.5V). This pin requires an external charge storage
capacitor C
≥
0.1µF. Larger value capacitors may be used
to reduce supply ripple. With multiple transceivers, the V
+
and V
–
pins may be paralleled into common capacitors.
U W
RX I
SC–
+
Slew Rate vs Load Capacitance
16
14
12
10
8
+SLEW
6
–SLEW
4
2
100
125
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
LOAD CAPACITANCE (nF)
LT1180A • TPC11
LT1180A • TPC10
Driver Output Waveforms
U
U
U
5
LINER [ LINEAR TECHNOLOGY ]
