4
LTC1347
1347fa
TYPICAL PERFOR A CE CHARACTERISTICS
UW
TEMPERATURE (°C)
0
SUPPLY CURRENT (mA)
60
20
16
14
12
10
8
6
4
2
0
1347 G04
20 7010
30
40
50
3 DRIVERS LOADED
R
L
= 3k
1 DRIVER LOADED
R
L
= 3k
V
CC
Supply Current
TEMPERATURE (°C)
–40
0
SHORT-CIRCUIT CURRENT (mA)
4
8
10
12
40
20
1347 G06
6
080
14
16
18
–20
60
20 100
I
SC
+
I
SC
–
Driver Short-Circuit Current
TEMPERATURE (°C)
0
LEAKAGE CURRENT (µA)
60
45
40
35
30
25
20
15
10
5
0
1347 G05
20 7010
30
40
50
V
OUT
= –20V
V
OUT
= 20V
Driver Leakage in Shutdown
Receiver Short-Circuit Current
TEMPERATURE (°C)
–40
10
SHORT-CIRCUIT CURRENT (mA)
30
60
0
40
60
1347 G07
20
50
40
–20
20
80
100
I
SC
–
I
SC
+
Driver Output Waveforms Receiver Output Waveforms
DRIVER
OUTPUT
R
L
= 3k
C
L
= 2500pF
1347 G08
1347 G09
RECEIVER
OUTPUT
C
L
= 51pF
INPUT
DRIVER
OUTPUT
R
L
= 3k
INPUT
V
CC
: 5V Input Supply Pin. Supply current is typically 80µA
in the Shutdown mode. This pin should be decoupled with
a 0.1µF ceramic capacitor.
GND: Ground Pin.
ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic
low puts the device in the Shutdown mode with all receiv-
ers kept alive, and the supply current is 80µA. All driver
outputs are in high impedance state. This pin cannot float.
V
+
: Positive Supply Output (RS232 Drivers).
V
+
≅ 2V
CC
– 1V. This pin requires an external capacitor C
= 0.1µF for charge storage. The capacitor may be tied to
ground or V
CC
. With multiple devices, the V
+
and V
–
pins
may be paralleled into common capacitors. 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
–
≅ – (2V
CC
– 1.5V). 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
UU
U
PI FU CTIO S
