The definitive reverse-engineering documentation for the
Apple Macintosh II power supply (1987)
Restoration Guide · First Edition
Coming Soon on AmazonWhen the Sony CR-45 was designed in 1987 for the original Apple Macintosh II, no public service documentation was ever released. No schematics. No component lists. No theory of operation. For nearly four decades, technicians restoring these machines had nothing to work with but a multimeter and intuition.
This book changes that. Built from over 150 hours of hands-on reverse engineering, every component has been physically identified, measured, and verified. Every circuit node has been traced. Every connector pin has been mapped. The result is the first and only complete technical reference for the CR-45 — from the AC input filter through the half-bridge forward converter to the regulated DC outputs that power the Macintosh II.
Whether you're restoring a vintage Mac II, studying 1980s Japanese power supply design, or simply curious about what's inside the machine that launched Apple into the professional computing era — this is your reference.
| Apple P/N | 699-0387 / 699-0389 |
| Sony P/N | 68-1073-5 |
| PCB | 1-621-969-11 (main board) |
| Topology | Half-bridge forward converter |
| AC Input | 100–120 VAC, 50/60 Hz |
| DC Outputs | +5V / 6A, +12V / 3A, −12V / 0.5A |
| PWM Controller | Fujitsu MB3759 (daughter board) |
| Architecture | Four boards — AC filter, main, PWM daughter, LED indicator |
| Date of Manufacture | February 1988 (unit under study) |