W7PUA DSP-10 Assembly

Diodes, Surface Mount, SOT-23 Package

sot23.jpg (48759 bytes)
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All surface mount diodes for the DSP-10 are housed in a SOT-23 package. SOT-23 packages are common and used for a variety of active devices.

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 Step 1:
Identify the location of the part. In the photo on the left, transistor Q102, also in a SOT-23 package, will be soldered to the PCB.

sot23_solder_02.jpg (98653 bytes)
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 Step 2:
Apply a very small amount of solder to only one pad. The single lead side of the SOT-23 is a good choice. The solder should form a slight bulge as shown in the photo at the left.

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 Step 3:
Position the part over the pads. Apply a small amount of no-clean flux to the component and pads. Holding the SOT-23 package with tweezers, heat the pad with the solder. Center the package as the solder melts. Remove the soldering iron while holding the component in place. Work as quickly as possible to minimize heating the component. Inspect your work. The component should be centered on the pads and lying flat against the PCB.

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 Step 4:
Solder the two remaining solder pads. Inspect your work with a magnifying glass or jeweler's loupe. Clean the area with Isopropyl Alcohol (IPA).

Assembly Notes:
  1. Work with one value at a time.

 

Designator Value Position (inch) Position (mm) Supplier Part Number Mfr. Data Sheet
[  ] D4 BAR74 (4.9 x 4.7 inch) (125.4 x 118.4 mm) Digi-Key BAR74ZXCT-ND Zetex
[  ] D5 BAR74 (2.3 x 1.2 inch) (57.8 x 31.4 mm)
[  ] D6 BAR74 (2.1 x 1.2 inch) (53.0 x 31.4 mm)
[  ] D105 BAR74 (1.1 x 2.7 inch) (27.9 x 67.3 mm)
[  ] D111 BAR74 (1.2 x 2.0 inch) (29.9 x 51.7 mm)
[  ] D112 BAR74 (1.8 x 2.3 inch) (44.8 x 59.1 mm)
[  ] D107 BAV74 (2.2 x 2.7 inch) (56.5 x 68.3 mm) Digi-Key BAV74ZXCT Zetex
[  ] D108 BAV74 (2.2 x 2.9 inch) (56.5 x 72.7 mm)
[  ] D109 BAV74 (2.2 x 3.1 inch) (56.5 x 77.1 mm)
[  ] D110 BAV74 (2.2 x 3.2 inch) (56.5 x 81.6 mm)
[  ] D1 HSMP-3804 (1.7 x 5.5 inch) (41.9 x 138.4 mm) HSMP-3814-BLK
[  ] D2 HSMP-3804 (0.3 x 4.7 inch) (7.6 x 119.1 mm)
[  ] D104 FMMV2101 (4.1 x 2.8 inch) (104.4 x 71.4 mm) Digi-Key FMMV2101CT Zetex
[  ] D113 FMMV2101 (4.0 x 2.6 inch) (101.9 x 65.7 mm)
[  ] D114 FMMV2101 (4.3 x 2.8 inch) (108.3 x 71.4 mm)
[  ] D115 FMMV2101 (4.2 x 2.6 inch) (106.4 x 65.7 mm)
[  ] D3 FMMV2103 (5.6 x 1.3 inch) (141.6 x 31.8 mm) Digi-Key FMMV2103CT Zetex

 

Page Last Revised: August 30, 2003