5
LTC1345
Y3 (Pin 22): Transmitter 3 Noninverting Output.
Z2 (Pin 23): Transmitter 2 Inverting Output.
Y2 (Pin 24): Transmitter 2 Noninverting Output
Z1 (Pin 25): Transmitter 1 Inverting Output.
Y1 (Pin 26): Transmitter 1 Noninverting Output.
V
EE
(Pin 27): Charge Pump Output. Connected to negative
terminal of capacitor C3.
C2
–
(Pin 28): Capacitor C2 Negative Terminal.
Transmitter and Receiver Configuration
S1 S2 TX# RX# REMARKS
0 0 — — Shutdown
1 0 1, 2, 3 1, 2 DCE Mode, RX3 Shut Down
0 1 1, 2 1, 2, 3 DTE Mode, TX3 Shut Down
1 1 1, 2, 3 1, 2, 3 All Active
Transmitter
INPUTS OUTPUTS
CONFIGURATION S1 S2 T Y1 AND Y2 Z1 AND Z2 Y3 Z3
DTE 0 1 0 0 1 Z Z
DTE 0 1 1 1 0 Z Z
DCE or All ON 1 X 0 0 1 0 1
DCE or All ON 1 X 1 1 0 1 0
Shutdown 0 0 X Z Z Z Z
Receiver
INPUTS OUTPUTS
CONFIGURATION S1 S2 OE B – A R1 AND R2 R3
DTE or All ON X 1 0 ≥0.2V 1 1
DTE or All ON X 1 0 ≤–0.2V 0 0
DCE 1 0 0 ≥0.2V 1 Z
DCE 1 0 0 ≤–0.2V 0 Z
Disabled X X 1 X Z Z
Shutdown 0 0 X X Z Z
15pFOE
R
50Ω
125Ω
Y
Z
Z
Y
T
125Ω
50Ω
50Ω
LTC1345 • F01
50Ω
B
A
V
OD
V
OS
V
OC
= (V
Y
+ V
Z
)/2
Figure 1. V.35 Transmitter/Receiver Test Circuit
Figure 2. Receiver Output Enable/Disable Timing Test Load
C
L
1k
LTC1345 • F02
S1
S2
V
CC
RECEIVER
OUTPUT
UU
U
PI FU CTIO S
FU CTIO TABLES
U
U
TEST CIRCUITS
