PBL 386 30/2

13

Figure 11. Single-channel subscriber line interface with PBL 386 30/2 and combination CODEC/filter.

RESISTORS: (Values according to IEC E96

series)

R

SG

= 0

Ω

1% 1/10 W

R

LD

= 49,9 k

Ω

1% 1/10 W

R

OV

= User programmable

R

LC

= 32,4 k

Ω

1% 1/10 W

R

REF

= 49,9 k

Ω

1% 1/10 W

R

R

= 64,9 k

Ω

1% 1/10 W

R

T

= 105 k

Ω

1% 1/10 W

R

TX

= 24,9 k

Ω

1% 1/10 W

R

B

= 22,1 k

Ω

1% 1/10 W

R

RX

= 52,3 k

Ω

1% 1/10 W

R

FB

Depending on CODEC / filter

R

1

= 604 k

Ω

1% 1/10 W

R

2

= 604 k

Ω

1% 1/10 W

R

3

= 249 k

Ω

1% 1/10 W

R

4

= 280 k

Ω

1% 1/10 W

R

RT

= 330

Ω

5% 2 W

R

= Line resistor, 40

Ω 1% match

R

= 10

Ω

1% 1/10 W,(Note 1)

CAPACITORS: (Values according to IEC

E96 series)

C

VB

= 100 nF

100 V 10%

C

VB2

= 150 nF

100 V 10%

C

VCC

= 100 nF

10 V 10%

C

TC

= 2,2 nF

100 V 10%

C

RC

= 2,2 nF

100 V 10%

C

HP

= 47 nF

100 V 10%

C

LP

= 150 nF

100 V 10%

C

TX

= 100 nF

10 V 10%

C

GG

= 220 nF

100 V 10%

C

1

= 330 nF

63 V 10%

C

2

= 330 nF

63 V 10%

DIODES:

D

VB

= 1N4448

D

VB2

= 1N4448

D

BB

= 1N4448

OVP:

Secondary protection ( e. g. Power

Innovations TISPPBL2). The ground

terminals of the secondary protection should

be connected to the common ground on the

Printed Board Assembly with a track as

short and wide as possible, preferable a

groundplane.

R

LC

R

RX

R

REF

R

LD

C

VCC

C

TX

PBL 386 30/2

R

TX

0

-

+

0

CODEC/

Filter

R

FB

SYSTEM CONTROL

INTERFACE

R

R

R

T

R

B

-

+

VCC

VCC

BGND

TIPX

VBAT

VBAT2

PLC

POV

PLD

VCC

PSG

NC

LP

DT

NC

DET

C1

C2

RRLY

HP

NC

RINGX

AGND

RSN

NC

REF

PTG

VTX

DR

NU

PBL 386 30/2

R

OV

R

SG

C

LP

C

1

R

4

C

2

R

3

C

HP

VB2

SLIC No. 2 etc.

C

RC

R

P2

R

P1

R

F2

R

F1

TIP

RING

OVP

C

GG

C

TC

VB

+12 V /+5V

K

R

C

VB

D

VB2

C

VB2

D

BB

VB

D

VB

R

RT

E

RG

R

2

R

1

Programmable overhead

voltage(POV)

With the POV function the overhead

voltage can be increased.

If the POV pin is left open the overhead

voltage is internally set to 3,2 V

hook and 1,3 V

R

and AGND, the overhead voltage can be

set to higher values, typical values can

be seen in figure 10. The R

corresponding V

are typical values for THD <1% and the

signal frequency 1000Hz.

Observe that the 4-wire output terminal

V

So if the gain 2-wire to 4-wire is 0dB,

3,2 V

side. Signal levels between 3,2 and

6,4 V

handled with the PTG shorted so that the

gain G

that the two-wire impedance, R

4-wire to 4-wire gain has to be recalcu-

lated if the PTG is shorted.

Please note that the maximum signal

current at the 2-wire side can not be

greater than 9 mA.

How to use POV:

1. Decide what overhead voltage(V

needed. The POV function is only

needed if the overhead voltage

exceeds 3,2 V

Peak

2. In figure 10 the corresponding R

the decided V

3. If the overhead voltage exceeds

3,2 V

gain has to be

changed to -6,02dB by connecting the

PTG pin to AGND. Please note that

the two-wire impedance, R

wire to 4-wire gain has to be recalcu-

lated.

NOTE:

1. R