91

Corporation

SIGNAL PROCESSING EXCELLENCE

Note:

1.

The common mode voltage is defined as the algebraic mean of the two voltages appearing at the

receiver input terminals with respect to the receiver circuit ground.

2.

Only one output drive pin per package will be shorted at any time.

3.

From 10% to 90% of steady state.

4.

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

5.

Outputs unloaded. Inputs tied to GND; T

6.

V

PINOUT

Pin 13 — R

Pin 14 — GND — Signal ground. Connected to

logic and chasis ground.

Pin 15 — V

Pin 16 — N.C. — No Connection.

Pin 17 — R

Pin 18 — N.C. — No Connection.

Pin 19 — N.C. — No Connection.

Pin 20 — T

Pin 21 — N.C. — No Connection.

Pin 22 — LOOPBACK — Active low; logic “1”

selects operating mode controlled by SELECT

A and SELECT B; logic “0” selects loopback

configuration for whatever operating mode is

selected by states of SELECT A and

SELECT B.

Pin 23 — T

Pin 24 — N.C. — No Connection.

Pin 25 — N.C. — No Connection.

Pin 26 — R

Pin 27 — N.C. — No Connection.

Pin 28 — V

FEATURES…

The SP306 is a single chip device that offers

both RS-422 and RS-423 serial interfaces. The

device can be programmed via two control mode

pins (7 and 8). In either operating mode, the

SP306 provides two full–duplex channels. A

loopback function is also provided for chip self–

test, which connects driver outputs to receiver

inputs with no external circuitry.

The RS-422 drivers convert TTL logic levels

into RS-422 differential output signals. The

RS-422 line driver outputs feature high source

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.

N.C.

N.C.

LOOPBACK

N.C.

N.C.

N.C.

N.C.

SP306

PIN ASSIGNMENTS

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; please refer to

SP306 Control Logic Configuration section for

truth table.

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

(pin 7) to select operating mode; please refer to

SP306 Control Logic Configuration section for

truth table.

Pin 9— T

Pin 10 — T

Pin 11 — N.C. — No Connection.

Pin 12— R