LT1180A/LT1181A
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Receiver Short-Circuit Current
Slew Rate vs Load Capacitance
50
40
30
20
10
0
16
14
12
10
8
–
RX I
+
SC
RX I
SC
+SLEW
6
–SLEW
4
2
0
–55
0
25
50
75 100 125
–25
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
TEMPERATURE (°C)
LT1180A • TPC10
Shutdown to Driver Outputs
Driver Output Waveforms
10V
DRIVER 1
OUTPUT
5V
GND
GND
DRIVER OUTPUT
RL = 3k
C
L = 2500pF
DRIVER 2
OUTPUT
–5V
DRIVER OUTPUT
L = 3k
–10V
R
ON/OFF PIN
INPUT
LT1180A • TPC13
LT1180A • TPC12
U
U
U
PI FU CTIO S
V+: Positive Supply Output (RS232 Drivers). V+ ≈ 2VCC
–
VCC: 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.
1.5V. This pin requires an external charge storage capaci-
tor C ≥ 0.1µF, tied to ground or VCC. 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.
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–: Negative Supply Output (RS232 Drivers). V– ≈ –(2VCC
– 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.
11801afb
5
Linear Systems [ Linear Systems ]
