71

Corporation

SIGNAL PROCESSING EXCELLENCE

PINOUT

PIN ASSIGNMENTS – RS232 MODE

Pin 1 — V

Pin 2 — R

Pin 3 — R

Pin 4 — N.C. — No Connection.

Pin 5 — T

Pin 6 — T

Pin 7 — SEL A — Select A; used with Select B

(pin 8) to select operating mode. Logic “0” on

both SEL A and SEL B selects RS-232 mode;

logic “1” on both SEL A and SEL B selects

AppleTalk™ mode.

Pin 8 — SEL B — Select B; used with Select A

(pin 7) to select operating mode. Logic “0” on

both SEL A and SEL B selects RS-232 mode;

logic “1” on both SEL A and SEL B selects

AppleTalk™ mode.

Pin 9— T

Pin 10 — T

Pin 11 — N.C. — No Connection.

Pin 12— R

Pin 13 — N.C. — No Connection.

Pin 14 — GND — Signal ground. Connected to

logic and chasis ground.

Pin 15 — V

Pin 16 — N.C. — No Connection.

Pin 17 — R

UART.

Pin 18 — N.C. — No Connection.

Pin 19 — T

TTL input from

UART.

Pin 20 — T

input from

UART.

Pin 21 — N.C. — No Connection.

Pin 22 — TxEN — Transmit Enable; Only

functional in Mac Mode.

Pin 23 — T

input from

UART.

Pin 24 — N.C. — No Connection.

Pin 25 — N.C. — No Connection.

SPECIFICATIONS

(T

PARAMETER

MIN.

TYP.

MAX.

UNIT

CONDITIONS

ENVIRONMENTAL AND MECHANICAL

Operating Temperature

0

+70

°C

Storage Temperature

–65

+150

°C

Package

28–pin SOIC

Note:

1.

RS-232 Mode, SELA = SELB = GND.

2.

V

3.

Macintosh™ AppleTalk™ Mode, SELA = SELB = +5V.

4.

Leakage current specification applies to both TxDO– and TxDO+; T

5.

From 10% to 90% of steady state.

6.

This is an absolute maximum rating. Normal operating levels are V

1

2

3

4

5

6

7

8

9

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

N.C.

SELECTA

SELECTB

N.C.

GND

N.C.

TXEN

N.C.

N.C.

SP303