LTC1349 LINER [Linear Technology], LTC1349 Datasheet - Page 4

• Manufacturer Part Number: LTC1349
• Description: 5V Low Power RS232 3-Driver/5-Receiver Transceiver with 2 Receivers Active in Shutdown
• Manufacturer: LINER [Linear Technology]

PI FU CTIO S
V
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 Shutdown mode, with receivers 4
and 5 kept alive and the supply current equal to 35µA. All
driver outputs and other receiver outputs are in high
impedance state. This pin can not float.
V
1V. This pin requires an external capacitor C = 0.1µF for
charge storage. The capacitor may be tied to ground or 5V.
LTC1349
4
TYPICAL PERFOR A CE CHARACTERISTICS
CC
+
: Positive Supply Output (RS232 Drivers). V
60
50
40
30
20
10
U
20
16
14
12
10
: 5V Input Supply Pin. Supply current is typically 35µA
8
6
4
2
0
–40
0
Receiver Short-Circuit Current
V
CC
–20
10
Supply Current
U
3 DRIVERS LOADED
20
1 DRIVER LOADED
0
TEMPERATURE (°C)
TEMPERATURE (°C)
I
SC
+
R
R
20
30
L
L
= 3k
= 3k
U
40
40
I
SC
–
60
50
W
LTC1349 • TPC04
LTC1349 • TPC07
80
60
U
100
70
C
L
= 2500pF
OUTPUT
OUTPUT
DRIVER
DRIVER
R
R
INPUT
L
L
= 3k
= 3k
45
40
35
30
25
20
15
10
5
0
0
Driver Leakage in Shutdown
Driver Output Waveforms
+
≅ 2V
10
CC
20
TEMPERATURE (°C)
–
30
V
V
With multiple devices, the V
leled into common capacitors. For large numbers of de-
vices, increasing the size of the shared common storage
capacitors is recommended to reduce ripple.
V
1.5V. This pin requires an external capacitor C = 0.1µF for
charge storage.
C1
pins require two external capacitors C = 0.1µF: one from
C1
charge pump efficiency, the capacitor’s effective series
resistance should be less than 20Ω.
OUT
OUT
40
–
: Negative Supply Output (RS232 Drivers). V
+
+
= –20V
= 20V
, C1
to C1
50
LTC1349 • TPC05
–
, C2
LTC1349 • TPC08
60
–
, and another from C2
+
, C2
70
C
–
L
: Commutating Capacitor Inputs. These
RECEIVER
= 2500pF
OUTPUT
INPUT
12
10
20
18
16
14
6
8
4
0
–40
Driver Short-Circuit Current
Receiver Output Waveforms
I
–20
+
SC
and V
+
I
SC
0
TEMPERATURE (°C)
–
+
–
to C2
20
pins may be paral-
40
–
. To maintain
60
–
LTC1349 • TPC06
≅ 2V
LTC1349 • TPC09
80
1349fa
CC
100
–