The plug into auto's cigarette lighter plug/cord for my Lowrance=20
I-finder color handheld GPS fried. Although the Internet search finds=20
lots of vendors selling these, there is no stock, and no prospects of=20
finding a replacement. I was able to open up the plug's case which=20
contains a .55" (14mm) x 1.05" (26mm) PCB with a 34063A, 8-SOIC package=20
switching regulator. First I made up a new board with a AS2954, TO-92=20
package 250 ma linear regulator (readily available from a nearby=20
supplier) , which borderline worked with the output voltage under load=20
2.5 volts, and blew the regulator once. Then, never had worked with=20
surface mount before, tried to remove the SOIC chip using a heat gun=20
from under side of the board, prying gently up on the chip. Was going=20
good, but then 2 pads tore loose from the PCB. At this time, looking for=20
a good solution with following thoughts:
1: Find a similar (3.3 VDC, 500ma) adapter off the shelf for a different=20
unit, splice the cable
2: Build up a Through the hole board with a Rohm BA 33CC0FP linear=20
regulator=20
(http://www.digikey.com/product-search/en?vendor=3D0&keywords=3Dba33dd0t).=
=20
Overall power consumption not an issue, but heating of the plug with PCB=20
inside is, but not thinking it's a concern. The plug is fused.
3: Build up a through the hole board with a switching regulator, but the=20
design of these is out of my turf. I see examples of 5 volt applications=20
in the data sheets, picture to adjust voltage, I would have to modify=20
the voltage divider resistors to the comparator pin, but wouldn't know=20
which inductor to select.

Any suggestions and comments appreciated. :)
--=20
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