9

07/23/02

Supertex, Inc. 1235 Bordeaux Drive, Sunnyvale, CA 94089 TEL: (408) 744-0100 FAX: (408) 222-4895 www.supertex.com

HV9906

Application Information

Universal Input Non-Isolated Constant 10mA Average Current LED Lamp Power Supply

PS

GATE

+Vin

Vdd

AGND

HV9906

1mH

220uH

Optional

12VDC to 400VDC

or

65VAC to 280VAC

1 to 8

LEDs

250

VN2460N8

1uF

to

6.8uF

0.01uF

10mA

PGND

NS

0.1uF

C1

D1 D2

D4 D3

C2

L1

L2

C3

C4

MURS120T3

D6

D7

R5

M1

U1

400V

1N4007

D5

MURS120T3

MURS120T3

R1

R2

R3

R4

8M

100k

700k

200k

Von

-

+

This circuit provides a constant average current output, which may

be used to power LED lamps. The circuit maintains a constant

average current and the value of C4 capacitor controls the peak-to-

peak ripple, which decreases with increasing capacitor value.

If current ripple is permissible then C4 may be omitted.

Universal Input Non-Isolated Constant 0.5A Average Current LED Lamp Power Supply

PS

GATE

+Vin

Vdd

AGND

HV9906

56uH

15uH

Optional

12VDC to 400VDC

or

65VAC to 280VAC

100

IRFBC30AF

1uF

to

6.8uF

0.033uF

PGND

NS

0.047uF

C1

D1 D2

D4 D3

C2

L1

L2

C3

C4

MURS160

D6

D7

R5

M1

U1

400V

1N4007

D5

MURS160

MURS160

R1

R2

R3

R4

8M

100k

900k

300k

Von

LED-1

Row 1

20mA

LED-9

Row 1

LED-1

Row 2

20mA

LED-9

Row 2

LED-10

Row 2

LED-1

Row 3

20mA

LED-10

Row 3

LED-9

Row 3

LED-1

Row 25

20mA

LED-9

Row 25

LED-10

Row 25

Q1

Q2

Q3

Q25

NPN Bipolar Transistor Array or Matched 2N2222

Negative Voltage

-

+

This circuit provides 0.5A constant average current output to power

249 LEDs , each operating at 20mA to form a large LED lamp or

array. The circuit maintains a constant average current and the

value of C4 capacitor controls the peak-to-peak ripple, which

decreases with increasing capacitor value.

If current ripple is permissible then C4 may be omitted.