9

Rev.4/08/02

SP3249E Intelligent +3.0V to +5.5V RS-232 Transceivers

© Copyright 2002 Sipex Corporation

Figure 15. Circuit for the connectivity of the SP3249E with a DB-9 connector

Figure 13. Charge Pump — Phase 3

–5V

+5V

–5V

+

+

++

–

–

–

–

Figure 14. Charge Pump — Phase 4

+10V

+

+

++

–

–

–

–

6. DCE Ready

7. Request to Send

8. Clear to Send

9. Ring Indicator

DB-9 Connector Pins:

1. Received Line Signal Detector

2. Received Data

3. Transmitted Data

4. Data Terminal Ready

5. Signal Ground (Common)

6

7

8

9

1

2

3

4

5

DB-9

Connector

22

0.1

µF

C5

+

0.1

µF

0.1

µF

GND

2

8

9

11

5k

Ω

5k

Ω

5k

Ω

16

21

14

5

6

7

R

R

R

R

R

R

10

12

24

19

18

T

T

T

T

T

T

15

17

T

T

T

T

SP3249E

3

1

23

4

C3

C4

+

+

C1+

C1-

C2+

C2-

V+

V-

0.1

µF

0.1

µF

+

C2

C1

+

13

20