BK Radio P150, Руководство по обслуживанию

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BK Radio Page 7-11
integrated circuit data
The two illustrations below show acceptable conductor spacing after solder flow. The spacing is not less
than 505 of the original width or less than 0.005”.
preferred
The solder holds the chip to the pads and normal
conductor spacings are maintained.
minimum acceptaBle
The spacing between the pads is reduced to 505 of the
original spacing.
The illustration below shows an unacceptable chip component, where the spacing between pads is
reduced by more than 50% because of the excess solder. This component must be reworked.
rework unacceptaBle
The spacing between the pads is reduced by more that
50% because of excess solder.
The illustrations below show acceptable components that have not floated higher than 0.020” above their
pads.
preferred
The solder height is minimal.
The fillet is concave.
There is good wetting.
The chip is raised less than 0.020”.
<0.020”
acceptaBle
The solder has floated the chip off its adhesive (if used)
but the amount of float is not greater than 0.020”.