ST ISA029V1 User Manual

STEVAL-ISA029V1

Compact power supply for DVD/set-top box demonstration board with three Vout (-30 V, +3.3 V, +12 V)

Data Brief

Features
■ Input voltage range: 85 VAC – 300 VAC
■ VOUT1= 12 V (±5%)
■	IOUT1= 1 A
■ VOUT2= 3.3 V (±2%)
■	IOUT2= 100 mA
■	VOUT3= -24 V (±10%)
■	IOUT3= 40 mA
■	Safety EN60950 compliant
■	EMI - conducted EN55022-B compliant	STEVAL-ISA029V1

Description

The STEVAL-ISA029V1 demonstration board is an isolated triple-output flyback converter, suitable for wide-range input voltage operation. The converter is based on the smart power VIPer53-E which, in a single package, integrates an enhanced current-mode PWM controller and a high-voltage MDmesh™ power MOSFET. The switching frequency is set to 60 kHz by means of an external RC network connected to a dedicated pin on the IC. The closed loop regulation is performed on the 12 V output using an optocoupler, which drives the COMP pin of the VIPer53-E. The 3.3 V output is post-regulated using a non-integrated low drop linear voltage regulator to achieve the required accuracy. The negative 24 V output is achieved by means of a discrete linear voltage regulator, made up of a Zener diode, a resistor and a PNP transistor.

September 2008	Rev 1	1/4
For further information contact your local STMicroelectronics sales office.		www.st.com

2/4

1

Board

.1 Figure

Board

schematic

C12

Come transistore di potenza:

schematic

BD140

BSS44

Q1

F1

2.2n

D1

STTH102

BD140

+3.3V

D2

R11

FUSE

J1

L1

DIODE BRIDGE

T1

-24V

5

4

C1

820

C2

J2

2

100n 400V

4

-

+

3

1

COUT1

D8

C16

U1

diagramSchematic

1

100n 400V

8

22u

LK112M33TR

1

TRANSIL - N.M.

ZENER 24V

100n

CON2

4.7u

2

R1

D3

3

C4

10mH

C15

4

RT1

C3

15k 2W

4.7n 400V

1

2

2

7

D4

STTH102

5

t

47u 400V

6

41

32

12

3

R12

330u

1

2

3

C5

7

50

D5

6

330

COUT2

100n

CON7

STTH110

4

5

+12V

D7

D6

STPS2H100

COUT3

TRANSFORMER

C14

1500u

R3

U2

R2

STPS1150

100n - NM

10

R4

R15

C6

5.6k

1

COMP

TOVL

8

180 1W

22u

1k

2

OSC

VDD

7

3

SOURCE

N.C.

6

C7

100n

C8

4

SOURCE

DRAIN

5

R5

1k

4.7n

VIPER53

U5

R6

R7

18k

1k

R8

C10

2.2k

PC817B

R9

C9

R13

D9

10n

470

STTH110

47k

C13

68n

C11

100n

3

N.M.

C17

TL431

2.2n 1kV

U4

1

2

R10

ISA029V1-STEVAL

4.7k