Sega CD Service Manual
The document behind this page is titled, on its own cover, MEGA-CD Maintenance Manual, Export — with the inner title page reading MEGA-CD Maintenance Manual, Europe — dated August 1992, Rev. A, 118 pages, Sega Enterprises, Ltd. It is the European/export manual for the first-generation Mega CD; the page title here uses the American name for the same machine.
It is by a wide margin the most complete Sega document on this wiki for the Model 1 unit, and it goes all the way down to PCB copper layers.
The scan carries a text layer.
Contents
[edit | edit source]| Section | Page |
|---|---|
| 1. Block diagram | |
| 2. Assembly drawing — 2-1 general reference number list | 4 |
| 2-2. Assembly list: 1001 top case; 1002 side cover and side knob; 1003 side cover; 1004 CD-ROM unit shield; 1005 main board; 1006 CD drive unit and sub board; 1007 bottom shield and front cover | 5–19 |
| 2-3. Procedure of disassembly and assembly | 20–31 |
| 3. Spare parts list | |
| 4. Accessories list | |
| 7. IC pin assignments — main board IC1/IC2, IC3, IC6, IC7/IC8, IC10/IC11, IC13, IC14/IC15; sub board IC1, IC2, IC3/IC4/IC5 | |
| 8. Parts list of PCB — 8-1 IC BD MEGA-CD MAIN BD EXPORT; 8-2 IC BD MEGA-CD SUB BD EXPORT; 8-3 ASSY MEGA-CD CONNECT BD EXPORT | 84–96 |
| 9. Schematic diagram — 9-1 main board; 9-2 sub board; 9-3 connect board | 91–103 |
| 10. Mount diagram — component side and solder side for all three boards | 104–109 |
| 11. PCB design spec — copper layer artwork, component side and solder side, for all three boards | 110–115 |
What this manual settles
[edit | edit source]- The Mega CD Model 1 is three boards, not one: a main board, a sub board and a connect board. Each has its own parts list, its own schematic and its own mount diagram. A capacitor list for this machine that does not say which board a designator belongs to is ambiguous.
- The IC complement of the main board, with pin assignments for each: IC1/IC2 HD68HC000CP-12 and the Sega custom MCE2 MB634120, part 315-5548; IC3 custom RF5C164A, part 315-5476A; IC6 MB3790; IC7/IC8 TC511664BZ-80; IC10/IC11 TC51832FL-10; IC13 LC8951; IC14/IC15 MB8464A-80. On the sub board: IC1 LC7883KM, IC2 LC7881M-C, IC3/IC4/IC5 µPC844G2.
- The Model 1 boards use a plain interleaved
Csequence with noCEseries — C1 through C58 in one run, with the electrolytics named in the description column (for example C41–C50 are 10 µF 16 V, Sega 150-0400 / 150-0400-01, and C51/C52 are 100 µF 6.3 V radial, 150-0401). This matches the Mega Drive Model 1 convention, not the Model 2 one. - Two part numbers are given for the same position in places — 150-0400 and 150-0400-01 for C41–C50 — which is Sega recording a second approved vendor, not a contradiction.
What this manual does not contain
[edit | edit source]- No fault tree or symptom table. This is a maintenance and parts manual: assemblies, disassembly, parts, schematics and board artwork. It does not tell you what a symptom means.
- No CD drive alignment or adjustment procedure.
- No Model 2 coverage. For the Sega CD (Model 2) see the Sega CD 2 / Mega CD 2 - Service Manual.
- Export/Europe machine only.
Pages that cite this document
[edit | edit source]- Sega CD (Model 1)
- Sega CD (Model 1) Maintenance Guide
- Sega CD (Model 1) Troubleshooting Guide
- Sega CD (Model 1) Capacitor Replacement Guide
Download: Sega CD Service Manual.pdf