AN3115

Component selection guidelines

Doc ID 16830 Rev 3

19/28

Equation 4

The current flows through R8, TR1 and R7 during fall time of 22 kHz tone and the power

dissipated by these passive components is 1/3 because the D.C. is 30 % (see Figure 11).

Figure 10.

Application circuit with PDC optional solution

L1

22 µH

C6

470 nF

C3

220 µF

Vin

12 V

to LNB

500 mA max

D2

BAT43

{

SDA

SCL

PDC

LX

Vup

Vcc -L

Vcc

VoRX

EXTM

ADDR

C8

220 nF

LNBH23L

TTX

P-GND

A -GND

D1

STPS130A

C10

220 nF

C4

470 nF

VoTX

ISEL

R2 (RSEL)

15 kOhm

Byp

C11

220 nF

DSQIN

D8

1N4148

*R7

22 Ohm

*C14

1 nF

*R5

2.2 kOhm

3.3 V

*TR1

BC317

C15

47 nF

R9

1.5 kOhm

(*)OPTIONAL components.

To be used only in case

of heavy capacitive load

*R8

150 Ohm

C2

100 nF

C1

100 µF

D3

1N4007

C5

N.C.

D6

N.C.

L1

22 µH

C6

470 nF

C3

220 µF

Vin

12 V

to LNB

500 mA max

D2

BAT43

{

SDA

SCL

PDC

LX

Vup

Vcc -L

Vcc

VoRX

EXTM

ADDR

C8

220 nF

LNBH23L

TTX

P-GND

A -GND

D1

STPS130A

C10

220 nF

C4

470 nF

VoTX

ISEL

R2 (RSEL)

15 kOhm

Byp

C11

220 nF

DSQIN

D8

1N4148

*R7

22 Ohm

*C14

1 nF

*R5

2.2 kOhm

3.3 V

*TR1

BC317

C15

47 nF

R9

1.5 kOhm

(*)OPTIONAL components.

To be used only in case

of heavy capacitive load

*R8

150 Ohm

C2

100 nF

C1

100 µF

D3

1N4007

C5

N.C.

D6

N.C.

TR1hfe

R

5

R

7

V

BE

V

D

V

BYP

I

C

+

-

-

=

TR1hfe

R

5

R

7

V

BE

V

D

V

BYP

I

C

+

-

-

=