76

77

BOARD LEVEL

HEAT SINKS

BOARD LEVEL

HEAT SINKS

641 SERIES

MAXIMUM PERFORMANCE NATURAL CONVECTION HEAT

SINK FOR ALL METAL-CASE SEMICONDUCTORS

601 & 603 SERIES

LOW-HEIGHT HEAT SINKS

NATURAL AND FORCED

CONVECTION CHARACTERISTICS

SEMICONDUCTOR MOUNTING HOLES

601 SERIES

(

EXTRUSION PROFILE 1284)

603 SERIES

(EXTRUSION PROFILE 1284)

K

E

F

Dimensions: in. (mm)

Dimensions: in. (mm)

641 SERIES

(EXTRUSION PROFILE 1371)

NATURAL AND FORCED

CONVECTION CHARACTERISTICS

SEMICONDUCTOR MOUNTING HOLES

A

K

Outline

Mounting

Standard

Dimensions

Height

Hole

Natural

Forced

Weight

P/N

in. (mm)

in. (mm)

Pattern

Convection

Convection

lbs. (grams)

641A

4.125 (104.8) x 3.000 (76.2)

1.000 (25.4)

(1) TO-3

36°C @ 15W

0.9°C/W @ 250 LFM

0.2900 (131.54)

641K

4.125 (104.8) x 3.000 (76.2)

1.000 (25.4)

None

36°C @ 15W

0.9°C/W @ 250 LFM

0.2900 (131.54)

Material: Aluminum Alloy, Black Anodized.

Available with a standard TO-3 mounting hole pattern predrilled for cost-effective mounting in limited-height

applications, the

641 Series provides maximum performance in natural convection with an optimized heat sink

surface area. The 641K type with an open channel area of 1.300 in. (33.0) and no predrilled mounting holes can

be adapted to meet mounting requirements for most metal case power semiconductor types.

MECHANICAL DIMENSIONS

MECHANICAL DIMENSIONS

Thermal Performance at Typical Load

BOARD LEVEL POWER SEMICONDUCTOR HEAT SINKS

DO-4/DO-5 Diodes

TO-3

Thermal Resistance

Part Number Description Length Width @ Forced Air Flow

678-39-S

Universal Heat Sink for TO Devices w/Screw Hole,

1.520"

2.362"

0.6°C/W @ 600 LFM

Black Anodize

(38.61mm) (60.00mm)

678-39-C

Universal Heat Sink for TO Devices w/ Clip,

1.520"

2.362"

0.6°C/W @ 600 LFM

Black Anodize

(38.61mm) (60.00mm)

UNIVERSAL 678 SERIES VERTICAL HEAT SINK FOR POWER DEVICES

Wakefield-Vette introduces

Universal 678 series, high performance, low cost and versatile heat sink

with screw or clip for all kinds of standard packages. This type of heat sink provides both vertical and

horizontal mounting options on PCB to accommodate natural and forced convection cooling method.

• Minimum assembly cost and labor - Spring Clips make

the mounting holes and fasteners obsolete in assembly

operations & reduce costs.

• Design Flexibility - Universal mountable and “one fits all”

give designers total freedom to fit their packaging designs

with ideal device pack style and to orient the heat sink to

meet their power dissipations with optimized cooling method.

(see page 7 of data sheet).

FEATURES AND BENEFITS

• Heat Sink: Aluminum Alloy 6063-T5 or Equivalent with

either degreased or black anodized finish

• Spring Clip: Music Wire, Per ASTM A228 with bright

nickel plating

• Solder Foot: Cold-rolled Steel, Per ASTM A-366 with

pure tin over copper strike. RoHS compliant.

• Insulator (Optional): t-Global H48-1, L37-3F and

H48-6S. The thickness of the insulating material not to

exceed 10 mil (0.01”).

SPECIFICATIONS

MECHANICAL DIMENSIONS

THERMAL PERFORMANCE

678-39-S & 678-39-C