CPC5622

6

www.ixysic.com

R03

2. Application Circuits

LITELINK can be used with telephone networks

worldwide. Some public telephone networks, notably

in North America and Japan require a resistive line

termination. Other telephone networks, such as in

Europe, China and elsewhere, require a reactive line

termination.

The application circuits that follow address both types

of line termination models. A reactive termination

application circuit that describes the TBR-21

implementation is shown in Figure 3 on page 8. This

circuit can be easily adapted for other reactive

termination needs.

2.1 Resistive Termination Application Circuit

Figure 2. Resistive Termination Application Circuit Schematic

¹This design was tested and found to comply with FCC Part 68 with this

Sidactor. Other compliance requirements may require a different part.

²Higher-noise power supplies may require substitution of a 220

H inductor,

Toko 380HB-2215 or similar. See the Power Quality section of IXYS

Integrated Circuits Division application note AN-146, Guidelines for

Effective LITELINK Designs

for more information.

³Optional for enhanced transhybrid loss.

application.

+

-

OH

RING

RING2

TX+

RX+

TX-

RX-

3.3 or 5V

C13

C14

C2

C4

R1

(R

80.6K

10

BR-

BR-

BR-

TIP

RING

U1

LITELINK

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

32

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

VDD

TXSM

TX-

TX+

TX

GND

RX-

RX+

SNP+

SNP-

RXF

RX

MODE

OH

RING

RING2

REFL

TXF

ZTX

ZNT

TXSL

BR-

NTS

GAT

NTF

DCS1

DCS2

ZDC

BR-

RPB

RXS

VDDL

DB1

BR-

BR-

A

A

A

C9

0.1μ

C16

10μ

FB1

600 Ω

200 mA

C1

1μ

(R

60.4K

5%

(R

200K

R13

(R

1M

5%

C10

0.01μ

500V

R15

1.69M

R20

2

6.49M

(R

6.49 M

(C

0.027μ

(R

130K

R3

1.5M

C7

(C

4

220pF

C8

220pF

(R

1.8M

1.8M

1.8M

1.8M

R4

68.1

BR-

NOTE: Unless otherwise noted:

Resistor values are in Ohms

All resistors are 1%.

Capacitor values are in Farads.

R14

(R

47

Q1

CPC5602C

(C

(R

3

8.2

R10

301

R18

3.32K

C18

R12

499K

(R

BR-

BR-

C15

0.01μ

500V

221K

(R

261K

0.1μ

0.1μ

0.1μ

0.1μ

R16

R8

R5

R75

BR-

C21

100p

R76

R22

R21

C12

R6

R44

R7

R45

(R

(R

(R

(R

(R

(R

(R

(R

(R

(R

(R

BR-

(C

4

R2

CPC5622