MAX3174CAI-T Maxim Integrated, MAX3174CAI-T Datasheet - Page 11

• Manufacturer Part Number: MAX3174CAI-T
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated
• Series: MAX3172, MAX3174r

Specifications of MAX3174CAI-T

• Data Rate: 240 Kbps
• Operating Supply Voltage: 3.3 V
• Supply Current: 0.2 mA
• Operating Temperature Range: 0 C to + 70 C
• Mounting Style: SMD/SMT
• Number Of Drivers: 1
• Number Of Receivers: 1

configured for V.10 or V.28 operation as a driver or
receiver
ble for use with the MAX3170 (clock/data transceiver)
and the MAX3171/MAX3173 (control transceiver). For
example, if X.21 mode is selected in DCE mode (M2 = 0,
M1 = 1, M0 = 1, and DCE/DTE = 1), the MAX3170,
MAX3171/MAX3173, and MAX3172/MAX3174 trans-
ceivers will all be placed in X.21 DCE mode.
The MAX3172/MAX3174 guarantee a logic HIGH
receiver output when the receiver input is shorted to
GND or when it is connected to a terminated transmis-
sion line with the driver disabled. The V.10 receiver
Figure 5. MAX3172/MAX3174 Termination Network Configurations
Figure 6. Typical V.11 Interface
GENERATOR
(Table
A
B
3). This mode-selection table is compati-
A
B
C
+3.3V Multiprotocol Software-Selectable
______________________________________________________________________________________
V.11 MODE
INTERCONNECTING
R1
52Ω
S1 ON
R2
52Ω
BALANCED
CABLE
S2 OFF
Cable Terminators and Transceivers
C*
127Ω
A′
B′
C′
TERMINATION
R3
100Ω
MIN
CABLE
LOAD
RECEIVER
A
B
Fail-Safe
R1
52Ω
S1 ON
R2
52Ω
V.35 MODE
S2 ON
threshold is between +25mV and +250mV. If the V.10
receiver input voltage is less than +25mV, R4OUT is
logic HIGH. If the V.10 receiver input is greater than
+250mV, R4OUT is logic LOW.
The V.28 receiver threshold is between +0.8V and
+2.0V. If the V.28 receiver input voltage is less than
+0.8V, R4OUT is logic HIGH. If the receiver input is
greater than +2.0V, R4OUT is logic LOW. If the driving
transmitter is disabled or disconnected, the receiver’s
input voltage is pulled to zero by its internal termination.
With the receiver thresholds of the MAX3172/MAX3174,
this results in a logic HIGH.
Older multiprotocol cable termination implementations
have been constructed using expensive relays with dis-
crete resistors, custom cables with built-in termination,
or complex circuit board configurations to route signals
to the correct termination. The MAX3172/MAX3174 pro-
vide a simple solution to this termination problem. All
required termination configurations are software selec-
table using four mode-control input pins (M2, M1, M0,
and DCE/DTE).
For high-speed data transmission, the V.11 specifica-
tion recommends terminating the cable at the receiver
C*
127Ω
R3
Applications Information
A
B
*NODE C IS PROVIDED IN NETWORKS 1,2,3.
R1
52Ω
S1 OFF
R2
52Ω
HIGH-Z MODE
S2 OFF
V.11 Termination
C*
127Ω
R3
11