MXL1543B Datasheet, PDF (9/18 Pages) Maxim Integrated Products – +5V Multiprotocol, 3Tx/3Rx, Software- Selectable Clock/Data Transceivers

+5V Multiprotocol, 3Tx/3Rx, Software-
Selectable Clock/Data Transceivers
Pin Description
PIN
NAME
FUNCTION
1
C1-
Capacitor C1 Negative Terminal. Connect a 1µF ceramic capacitor between C1+ and C1-.
2
C1+
Capacitor C1 Positive Terminal. Connect a 1µF ceramic capacitor between C1+ and C1-.
3
V_DD
Generated Positive Supply. Connect a 4.7µF ceramic capacitor to ground.
4
V_CC
+5V Supply Voltage (±5%). Decouple with a 1µF capacitor to ground.
5
T1IN
Transmitter 1 TTL-Compatible Input
6
T2IN
Transmitter 2 TTL-Compatible Input
7
T3IN
Transmitter 3 TTL-Compatible Input
8
R1OUT
Receiver 1 CMOS Output
9
R2OUT
Receiver 2 CMOS Output
10
R3OUT
Receiver 3 CMOS Output
11
M0
Mode-Select Pin with Internal Pullup to V_CC
12
M1
Mode-Select Pin with Internal Pullup to V_CC
13
M2
Mode-Select Pin with Internal Pullup to V_CC
14
DCE/DTE
DCE/DTE Mode-Select Pin with Internal Pullup to V_CC
15
R3INB
Noninverting Receiver Input
16
R3INA
Inverting Receiver Input
17
R2INB
Noninverting Receiver Input
18
R2INA
Inverting Receiver Input
19
T3OUTB/R1INB Noninverting Transmitter Output/Noninverting Receiver Input
20
T3OUTA/R1INA Inverting Transmitter Output/Inverting Receiver Input
21
T2OUTB
Noninverting Transmitter Output
22
T2OUTA
Inverting Transmitter Output
23
T1OUTB
Noninverting Transmitter Output
24
T1OUTA
Inverting Transmitter Output
25
GND
Ground
26
V_EE
Generated Negative Supply. Connect a 4.7µF ceramic capacitor to ground.
27
C2-
Capacitor C2 Negative Terminal. Connect a 1µF ceramic capacitor between C2+ and C2-.
28
C2+
Capacitor C2 Positive Terminal. Connect a 1µF ceramic capacitor between C2+ and C2-.
Detailed Description
The MXL1543B is a three-driver/three-receiver, multipro-
tocol transceiver that operates from a single +5V supply.
The MXL1543B, along with the MXL1544/MAX3175 and
MXL1344A, form a complete software-selectable DTE or
DCE interface port that supports the V.28 (RS-232),
V.10/V.11 (RS-449/V.36, EIA-530, EIA-530A, X.21), and
V.35 protocols. The MXL1543B transceivers carry the
high-speed clock and data signals, while the
MXL1544/MAX3175 transceivers carry serial interface
control signaling. The MXL1543B can be terminated by
the MXL1344A software-selectable resistor termination
network or by a discrete termination network. The
MXL1543B features a 0.5µA no-cable mode, true fail-safe
operation, and thermal shutdown circuitry. Thermal shut-
down protects the drivers against excessive power dissi-
pation. When activated, the thermal shutdown circuitry
places the driver outputs into a high-impedance state.
Mode Selection
The state of the mode-select pins M0, M1, and M2
determines which serial interface protocol is selected
(Table 1). The state of the DCE/DTE input determines
whether the transceiver will be configured as a DTE or
DCE serial port. When the DCE/DTE input is logic
HIGH, driver T3 is activated and receiver R1 is dis-
abled. When the DCE/DTE input is logic LOW, driver T3
is disabled and receiver R1 is activated. M0, M1, M2,
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