Conclusion

The higher the ambient temperature, the board temperature,

and the power dissipation of the LM3404HV, the more likely

that the PSOP-8 package will be required in order to maintain

the junction temperature below T

thermal stress becomes greater and the PCB area becomes

smaller, the more likely that the LM3404HV will need to be

mounted on an MCPCB.

The results presented in this application note are intended to

guide the user in selecting the correct package and configu-

ration for a high powered LED driver such as the LM3404HV.

The general trends observed are valid for other applications,

but will not correlate directly to other circuits or applications.

Bill of Materials

ID

Part Number

Type

Size

Parameters

Qty

Vendor

U1

LM3404HVMR

LED Driver

PSOP-8

75V 1A

1

NSC

L1

SLF10145T-470M1R4

Inductor

10.0 x 10.0 x 4.5mm

47µH, 1.4A, 0.1

Ω

1

TDK

D2

CMSH2-60

Schottky Diode

SMB

60V 2A

1

Central Semi

Cf

VJ0603Y104KXXAT

Capacitor

0603

100nF 10%

1

Vishay

Cb

VJ0603Y103KXXAT

Capacitor

0603

10nF 10%

1

Vishay

Cin1, Cin2

C4532X7R2A105M

Capacitor

1812

2.2µF 100V

2

TDK

Co

C3216X7R2A474M

Capacitor

1206

0.47µF 100V

1

TDK

Rsns

ERJ8BQFR20V

Resistor

1206

0.2Ω 1%

1

Panasonic

Ron

CRCW06035363F

Resistor

0603

536k

Ω1%

1

Vishay

PCB Layout

30019205

Top Layer

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