4-31

Basic Application Circuit

Voice Only 28 Lead PLCC Package

TIP

RING

FIGURE 27. UniSLIC14 VOICE ONLY BASIC APPLICATION CIRCUIT

ZT

RSYNC_REV

ILIM

ROH

RD

SHD

GKD_LVM

C1

C2

C3

RRLY

CH

BGND

VBH

VBL

RDC_RAC

CDC

DR

DT

CRT_REV_LVM

+5V

+5V OR

RELAY

-24V

-48V

RING

TIP

VBAT

RING

CONTROL LOGIC

CODEC/FILTER

U1

U2

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

26

28

PTG

GENERATOR

C7

+5V

AGND

25

SPM

27

+12V

OPTIONAL

WHEN USING A NON-DSP CODEC.

NON-DSP CODEC’s.

NOT REQUIRED FOR DSP CODEC.

REQUIRED FOR DSP CODEC’s

TABLE 2. BASIC APPLICATION CIRCUIT COMPONENT LIST

COMPONENT

VALUE

TOLERANCE

RATING

U1 - SLIC

UniSLIC14 Family

N/A

N/A

U2 - Dual Asymmetrical Transient Voltage Suppressor

TISP1072F3

N/A

N/A

RP (Line Feed Resistors)

30

Ω

Matched 1%

2.0W

R1 (RDC_RAC Resistor)

21k

Ω

1%

1/16W

R2, R3

2M

Ω

1%

1/16W

R4 (RD Resistor)

41.2k

Ω

1%

1/16W

R5 (ROH Resistor)

38.3k

Ω

1%

1/16W

R6 (RILIM Resistor)

33.2k

Ω

1%

1/16W

R7 (RSYNC_REV Resistor)

34.8k

Ω

1%

1/16W

R8 (RZT Resistor)

107k

Ω

1%

1/16W

R9, R10, R11

20k

Ω

1%

1/16W

R12

400

Ω

5%

2W

C1 (Supply Decoupling), C2

0.1

µF

20%

10V

C5 (Supply Decoupling)

0.1

µF

20%

50V

C6 (Supply Decoupling)

0.1

µF

20%

100V

C4, C7, C10, C11

0.47

µF

20%

10V

C3

4.7

µF

20%

50V

C8, C9

2200pF

20%

100V

D1, Recommended if the VBL supply is not derived from the VBH Supply

1N4004

-

-

Current Limit = 31mA, Synthesize Device Impedance = 540

Ω (600 - 60), with 30Ω protection resistors, impedance across Tip and Ring terminals =

600

Ω. Where applicable, these component values apply to the Basic Application Circuits for the HC55120, HC55121, HC55130/1, HC55140/1,

HC55142/3 and HC55150/1. Pins not shown in the Basic Application Circuit are no connect (NC) pins.

HC55120, HC55121, HC55130, HC55131, HC55140, HC55141, HC55142, HC55143, HC55150, HC55151