Mounting instructions for Flangeless Packages

Heat sink mounting of any device in the Flangeless Package family follows the same

process details outlined in this document.

Heat Sink Surface:

1. The heat sink surface should be smooth, free

of nicks and burs; in addition it should be flat to

≤.001in./in TIR, (Total Indicator Run out) and be

finished to ~ 68µ CLA, (Center Line Average).

2. Must be free of solder balls, metal shavings and

any foreign objects or material.

Device Preparation:

1. The leads should be prepared with an “s” bend, as

shown in Figure 25 prior to mounting on the heat sink.

2. The BeO surface of the device must be

free of any foreign objects or material.

3. The BeO surface must be coated with a

thin and uniform film of thermal compound.

4. For commercial manufacturing the

suggested method for thermal compound

application is to apply the compound using

a screen printer. This process insures con-

sistent and repeatable performance with

minimum effort.

Mechanical Attachment:

1. The four screws (1-2-3-4), as shown in

Figure 24, should be installed and seated,

then torqued to one-half the specification,

in the sequence shown. First screw 1 then

screw 2, 3 and 4.

2. Then complete the process by tighten-

ing to the full specification in the same

manner.

3. The torque spec is 8in.lb. ± 1lb.

(0.9Nm)

Lead Attachment:

1. The leads may now be soldered to the

PCB

2. Maximum lead temperature must not

exceed 300oC for 10s.

3. For lead free use 96.5 % tin, 3% silver,

and 0.5% copper.

4. Non-lead Free use 2% Silver, 62% Tin,

36% lead (sn62).

Figure 24, Top and Side View of a T3 device

Figure 25, Stress Relief bend

DRF100