SP331 Datasheet, PDF (1/13 Pages) Sipex Corporation – Programmable RS-232/RS-485 Transceiver

®
SP331
Programmable Dual RS-232/RS-485Transceiver
FEATURES
■ +5V Only Operation
■ Software Programmable RS-232 or RS-485
Selection
■ Four RS-232 Transceivers in RS-232 Mode
■ Two RS-485 Full-Duplex Transceivers in
RS-485 Mode
■ Two RS-232 Transceivers and One RS-485
Transceiver in Dual Mode
■ Self-Testing Loopback Mode
TI4 1
SEL_B 2
TX4 3
TX3 4
VCC 5
TX1 6
TX2 7
GND 8
C1+ 9
V+ (VDD) 10
C2+ 11
C1– 12
C2– 13
V– (VSS) 14
28 TI3
27 TI2
26 TI1
25 SEL_C
24 SEL_A
23 SEL_D
22 RX4
21 RX3
20 RX2
19 RX1
18 RI4
17 RI3
16 RI2
15 RI1
■ Full Driver Tri-State (Hi-Z) Control
Now Available in Lead Free Packaging
■ Ideal for RS-232 to RS-485 conversion
DESCRIPTION
The SP331 is a programmable RS-232 and/or RS-485 transceiver IC. The SP331 contains four
drivers and four receivers when selected in RS-232 mode; and two drivers and two receivers
when selected in RS-485 mode. The SP331 also contains a dual mode which has two RS-232
drivers/receivers plus one differential RS-485 driver/receiver.
The RS-232 transceivers can typically operate at 230kbps while adhering to the RS-232
specifications. The RS-485 transceivers can operate up to 10Mbps while adhering to the RS-485
specifications. The SP331 includes a self-test loopback mode where the driver outputs are
internally configured to the receiver inputs. This allows for easy diagnostic serial port testing
without using an external loopback plug. The RS-232 and RS-485 drivers can be disabled
(High-Z output) by controlling a set of four select pins.
TYPICAL APPLICATION CIRCUITS
+5V
0.1µF
0.1µF
+5V
+5V
TTL/CMOS
TTL/CMOS
TTL/CMOS
TTL/CMOS
TTL/CMOS
TTL/CMOS
TTL/CMOS
TTL/CMOS
5
9 _C1+
12 _C1-
11 _C2+
VCC
10
V+
SP331
14
V-
13
C2-
24
2 ^{SEL A}
SEL B
Vcc
400KΩ
26 TI1
T1
27 _{TI2 Vcc}
400KΩ
28 TI3
T3
1 _TI4
0.1µF
23
SEL D
TX2 7
TX1 6
TX4 3
TX3 4
RI2 16
19 RX1
R1
15KΩ
RI1 15
20
RX2
15KΩ
RI4 18
21 RX3
R3
15KΩ
RI3 17
22 _RX4
8 _GND
15KΩ
25
SEL C
0.1µF
0V
RS-485
RS-485
RS-485
RS-485
RS-485
RS-485
RS-485
RS-485
0V
Date: 03-04-05
Programmable Dual RS-232/RS-485 Transceiver
1
© Copyright 2005 Sipex Corporation