Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com

SP3238E_100_020111

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Table 1. Device Pin Description

NAME

FUNCTION

PIN NUMBER

C2+

Positive terminal of the symmetrical charge-pump capacitor C2.

1

GND

Ground.

2

C2-

Negative terminal of the symmetrical charge-pump capacitor C2.

3

V-

Regulated -5.5V output generated by the charge pump.

4

T

RS-232 Driver Output.

5

T

RS-232 Driver Output.

6

T

RS-232 Driver Output.

7

R

RS-232 receiver input.

8

R

RS-232 receiver input.

9

T

RS-232 Driver Output.

10

R

RS-232 receiver input.

11

T

RS-232 Driver Output.

12

ONLINE

Apply logic HIGH to override

AUTO ON-LINE® circuitry keeping drivers

active (SHUTDOWN must also be logic HIGH, refer to Table 2).

13

SHUTDOWN Apply logic LOW to shut down drivers and charge pump.

This overrides all

AUTO ON-LINE® circuitry and ONLINE (Refer to table 2).

14

STATUS

TTL/CMOS Output indicating if a RS-232 signal is present on any receiver

input.

15

R

Non-Inverting receiver - 1 output, active in shutdown.

16

T

TTL/CMOS driver input.

17

R

TTL/CMOS receiver output.

18

T

TTL/CMOS driver input.

19

R

TTL/CMOS receiver output.

20

R

TTL/CMOS receiver output.

21

T

TTL/CMOS driver input.

22

T

TTL/CMOS driver input.

23

T

TTL/CMOS driver input.

24

C1-

Negative terminal of the symmetrical charge-pump capacitor C1.

25

Vcc

+3.0V to +5.5V supply voltage.

26

V+

Regulated +5.5V output generated by the charge pump.

27

C1+

Positive terminal of the symmetrical charge-pump capacitor C1.

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