Editing Macintosh LC 550 (section)

== PCB Architecture & Service Documentation ==

The LC 550 shares its logic board design with the Color Classic II, using Apple part number 820-0368-A:

=== Logic Board ===
The LC 550 logic board features:
* '''Motorola 68030''' processor at 33 MHz with full 32-bit data bus
* '''Optional 68882 FPU''' socket for floating-point operations
* '''Enhanced LC PDS slot''' supporting both 96-pin and 114-pin expansion cards
* '''72-pin SIMM slot''' for memory expansion up to 36 MB

=== Analog Board ===
The analog board provides:
* Power regulation for +5V, +12V, -12V rails
* CRT drive circuits for the 14" Trinitron display
* Audio amplification for stereo speakers
* Deflection circuits for display geometry

=== Apple Service Manual ===
<pdf width="800" height="500">File:Lc 520.550.575.pdf</pdf>

Service documentation is available on the [[:Category:Apple Service Source|Apple Service Source]] page.