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TGoddard/SP332/9617R0

SP332 RS-232/RS-485 Multi-Mode Serial Transceiver

© Copyright 2000 Sipex Corporation

SP332

RS-232/RS-485 Multi-Mode Serial Transceiver

RS-232 Mode

Full Duplex RS-485

s +5V-Only Single Supply Operation

s 4 Drivers, 4 Receivers RS-232

s 2 Drivers, 2 Receivers RS-485

s Loop Back Function for Self Test

s 28 Pin SOIC Packaging

DESCRIPTION…

The SP332 is a monolithic device that contains both RS-232 and RS-485 line drivers and

receivers. The configuration of the SP332 can be changed at any time by changing the logic

state of two control input pins. The device also includes a loop back function which internally

connects driver outputs to receiver inputs for a chip self test. A Sipex-patented charge pump

(5,306,954) allows +5V-only operation.

SEL A

TTL/CMOS

TTL/CMOS

TTL/CMOS

0.1

µF

0.1

µF

C1+

C1-

C2+

C2-

1

SEL B

2

+5V

VCC

5

GND

8

9

11

12

13

19

20

22

24

26

27

28

TTL/CMOS

TTL/CMOS

TTL/CMOS

TTL/CMOS

T1

T3

R1

RS-485/RS-232

RS-485/RS-232

RS-485/RS-232

TTL/CMOS

0.1

µF

0.1

µF

V+

V-

TTL/CMOS

SHUT

DOWN

RS-485/RS-232

RS-485/RS-232

RS-485/RS-232

4

6

7

10

14

15

16

23

25

3

RI1

RI2

TX3

TX4

TX1

TX2

TI1

TI2

TI3

TI4

RX1

RX2

TTL/CMOS

21

R3

17

18

RI4

RI3

RX3

RX4

Vcc

Vcc

LOOP

BACK

RS-485/RS-232

RS-485/RS-232

+5V

+5V

TTL/CMOS

TTL/CMOS

+5V

GND

TTL/CMOS

TTL/CMOS

TTL/CMOS

TTL/CMOS

TTL/CMOS

0.1

µF

0.1

µF

VCC

V+

V-

TTL/CMOS

SHUT

DOWN

RS-232

TTL/CMOS

TTL/CMOS

TTL/CMOS

TTL/CMOS

T1

T2

T3

T4

TX1

TX2

TX3

TX4

TI1

TI2

TI3

TI4

RI1

RI2

RI3

RI4

RX1

RX2

RX3

RX4

1

3

4

5

6

7

8

10

0.1

µF

0.1

µF

C1+

C1-

C2+

C2-

9

11

12

13

14

15

16

17

18

19

20

21

22

23

SEL B

2

SEL A

24

25

26

27

28

R1

R2

R3

R4

5K

Ω

5K

Ω

5K

Ω

5K

Ω

400K

Ω

Vcc

400K

Ω

Vcc

400K

Ω

Vcc

400K

Ω

Vcc

RS-232

RS-232

RS-232

RS-232

RS-232

RS-232

RS-232

LOOP

BACK

0V

0V

SP332

SP332

®