2

FN9007.7

April 13, 2005

Functional Block Diagram

Typical Application Schematic for 4 Line VoIP

NOTES:

3. C2 fit as close as possible to transformer.

4. T1 = IFLY0012 contacts: Coilcraft: (847) 516-7377 GCI Technology: (972) 423-8411 ext. 245

5. For custom specific designs or questions please contact Intersil at 1-888-INTERSIL or 321-724-7143.

OSC

SD

CT

SYNC

CS

FB

11

12

13

GATE

PVCC

PWRGND

S

RQ

CLK

R

Q

TFF

LEADING

EDGE

BLANKING

2

3

ILIM

+

-

SOFT-

START

CLK

ENPWM

LVC

POR

SOFT-START

VREF

ICLCOMP

ICSCOMP

UVLO

+

-

+

-

ERROR

AMP

CS

COMP

4

5

9

VCC

GND

VOLTAGE

REFERENCE

IBIAS

200K

1

14

10

VREF

+

-

NFB_IN

76

8

NC

NFB-OUT

NFB

AMP

9V TO

VIN

C1A-E

2.2

µF

35V

C2

1

µF

50V

0

0 0 000

C3

1

µF

16V

GND

+5V

VCC

±10%

+

0

0

0

R7

220

C8

330pF

D2

MUR5160T3

1

2

3

4

14

13

12

11

5

6

10

9

7

8

SD

SYNC

CT

COMP

FB

NFB

NFB_IN

GATE

GNDP

GND

CS

NC

ISL6401

2

7

3

6

4

5

GND

+

C10A

330

µF

35V

D1

MUR5120T3

-24V,

-72V,

120mA

120mA

R4A

43.5K

IFLY0012

T1

SEC

VOUT1

VOUT2

R5

0.025

1W

R6

100

Q1

IRLR2905

C7

1000pF

C5

220pF

C6

0.027

µF

R1

20K

R2

10K

R3

1.24K

E

C4

560pF

20V

PRI

8

1

C9

100

µF

100V

C12

0.1

µF

C11

1

µF

R4B

143K

ISL6401