18

LTC2844

sn2844 2844fs

Figure 25. Controller-Selectable Multiprotocol DTE/DCE Port with RL, LL, TM and DB-25 Connector

TYPICAL APPLICATIO S

D2

D1

LTC2845

DTE_RTS/DCE_CTS

DTE_DTR/DCE_DSR

DTE_DSR/DCE_DTR

DTE_DCD/DCE_DCD

DTE_CTS/DCE_RTS

D3

R2

R1

R4

R3

LTC2846

DTE_LL/DCE_RI

DTE_RI/DCE_LL

DTE_TM/DCE_RL

DTE_RL/DCE_TM

DTE_TXD/DCE_RXD

DTE_SCTE/DCE_RXC

DTE_TXC/DCE_TXC

DTE_RXC/DCE_SCTE

DTE_RXD/DCE_TXD

M0

M1

M2

DCE/DTE

GND

2844 F26

C2

1

µF

R1

13k

C1

1

µF

C6

10

µF

C3

1

µF

C4

3.3

µF

D4

5V

SHDN

3.3V

CHARGE

PUMP

BOOST

SWITCHING

REGULATOR

L1

5.6

µH

33

7

35

4

36

D1

MBR0520

3

5

6

8

9

10

11

12

13

14

15

16

18

19

1, 19

2

3

4

5

6

7

8

10

9

D5

18

DCE/DTE

D4ENB

R4EN

20

15

16

NC

3.3V

23

R5

17

22

21

25

24

26

27

28

29

30

31

32

33

32

31

30

29

28

27

26

25

24

23

22

21

20

34

35

36

C5

10

µF

C9

1

µF

C7

1

µF

C8

1

µF

M0

M1

M2

DCE/DTE

M0

M1

M2

11

12

13

14

D1

D2

D3

R1

R2

R3

T

T

T

T

T

C10

1

µF

R2

4.3k

5V

18

*

*OPTIONAL

21

25

LL

LL

RL

RL

TM

TM

RI

RI

2

14

24

11

15

12

17

9

3

1

4

19

20

8

23

10

6

22

5

13

7

16

TXD A

TXD B

SCTE A

SCTE B

RXD A

RXD B

RXC A

RXC B

RXC A

RXC B

RXD A

RXD B

RTS A

RTS B

DTR A

DTR B

CTS A

CTS B

DSR A

DSR B

CTS A

CTS B

SG

SHIELD

DB-25

CONNECTOR

TXC A

TXC B

SCTE A

SCTE B

TXD A

TXD B

TXC A

TXC B

DCD A

DCD B

DSR A

DSR B

RTS A

RTS B

DCD A

DCD B

DTR A

DTR B

DTE

DCE

3.3V