This is an old revision of the document!
LN has observed (not sure if always true): “cmos…yamaha part starts with a 3 (nmos parts start with 2)”
"A quick lesson in yamaha datecodes: (not sure if the cutoff was 1989, 1990 or 1991 but its one of those) Pre cutoff: yl ww LL r Post cutoff: Yyww LLlr Y = year most significant (9 or 0 or 1 for 199x or 200x or 201x) y = year least significant (2 = 1982, 3 = 1983 ... etc ... 9 = 1989) (0 = 1990 for only chips pre-cutoff?) LLl = lot code/batch code? ww = week within year r = die revision"
From LN
Chip Codename Package Manufacturers/Fabs Die Revisions Years SEEN YM21280 OPS QUIP YM21290 EGS QUIP YM2142 GE8 DIP YM2148 MIDIC? DIP 5 H 1985 YM2149F SSG DIP 3, 4, 5, A, X G 1985-1993 YM2151 OPM DIP 3, 4, 5, 6, 8, E, X, Z G 1984-1992 YM2154 RYP4 QUIP YM2163 DSG DIP YM2164 OPP DIP 2, 7, 8, X, Y C 1985-1986 YM2167 OPP2 YM2203C OPN DIP 5, A, G F, H 1987-1994 YM2413 OPLL NDIP, F, M 5, 7, E G 1988-1997 YM2413A OPLL NDIP YM2413B OPLL NDIP YM2414B OPZ DIP 1, X E 1988 YM2420 OPLL2 NDIP 6 A 1989 http://madscient.hatenablog.jp/entry/2013/07/10/032236 YM2608B OPNA SDIP G O, P 1994-1995 YM2610 OPNB SDIP I, Y H, J 1989-1993 YM2610B OPNB SDIP I I, K 1992-1994 YM2612 OPN2 DIP 1, 2, 3, A, I, X, Y B 1988-1992 YM3420 OPU YM3438 OPN2C DIP A, X A 1989-1994 YM3439 SSGC D, S YM3526 OPL DIP 3, 7 E 1985-1986 YM3806 OPQ YM3812 OPL2 DIP,F 3, 5, 7, E B 1987-1994 Y8950 MSX-AUDIO SDIP 7 G 1986-1988 VRC VII VRC7 DIP I D 1990-1997 YM7116 OPK DIP http://www.dtech.lv/techarticles_yamaha_opk.html YM7129 OPK2 DIP YM7137 OPJ DIP A I 1990 YMF262 OPL3 M, F (D?),E,F,G C -1994 YMF271 OPX F L C 1993 YMF276 OPN2L M G B 1993-1994 YMF278B OPL4 YMF281 OPLLP D H A 1998 (-2005?) YMF288 OPN3 M E D 1994-1995 YMF289 OPL3L YMF292 SCSP YMF297 OPN3/OPL3 YMZ284 SSGL YMZ285 ?SSGLL? YMZ294 ?SSGL2? YMF701 OPL3-SA YMF704C OPL4-ML S G 6 1997 YMF711 OPL3-SA2 YMF715 OPL3-SA3 YMF721 OPL4-ML2 S G 8 2001 YMF724 DS-1 YMF725 AC97 codec for DS-1 YMF727 AC3F2 YMF738 sensaura reverb YMF740C DS-1L YMF743 AC97 2.1 codec YMF744B DS-1S YMF752 AC97 2.1 codec + samplerate converter YMF753 AC97 2.2 codec YMF754 DS-1E YM3012 DAC-MS NDIP I, 8 F (1984-?)1991-1993 YM3014 DAC-SS NDIP Z C 1985 YM3014B DAC-SS NDIP ? D 1990 YM3016 DAC(CD) D I A 1993 Sega parts by yamaha: YM2602B 315-5124 SDIP 6 B 1987 8045B 315-5308 QFP Z B 1989 8048 315-5309 QFP X, Y, L? C 1988-1991 YM7101 315-5313 QFP 4, A, E, H, L, O, X, Y C, D, E 1989-1991 FC1001 315-5313A QFP H, L C 1992 8045C 315-5364 QFP A D 1992 ? 315-5402 ? 315-5433 QFP NO YAMAHA STYLE MARKING 1991 FC1004 315-5487-01 QFP Z E 1992 FC1004 315-5487 QFP H I 1992 FC1004 315-5660 QFP G, H M 1993-1996 FC1004-X 315-5660-10 QFP H M 1993 This might be the same as plain FC1004 rev M TC6158AF 315-5685 QFP NO YAMAHA STYLE MARKING FF1004 315-5700 QFP A H 1995 T9N13BF 315-5786 QFP NO YAMAHA STYLE MARKING FJ3002 315-5960 QFP C F 1996 Index: Package codes: D = NDIP/DIP M = SOIC F = QFP (sometimes soic, mismarked?) S = QFP44 Manufacturers/Fabs: oldstyle: 1 = 2 = Sharp? 3 = 4 = L = Hitachi 2 5 = Sharp (NDIP) 6 = Hitachi 7 = 8 = Hitachi or ROHM (ndip)? X = Y = Hitachi? newstyle: A = Sharp 2 C = Hitachi 2 D = E = Hitachi 1 F = Fujitsu G = Hitachi 1 H = Sharp 1 I = Sharp (verified from multiple chips) L = 4 = Hitachi 2 O = both: Z = Fujitsu Yamaha datecode format: "Old style": YM WW LL R "New style" YYWW MLLR YY = last 2 digits of year Y = last digit of year WW = week M = manufacturer or fab (code differs for old vs new style?) LL = lotcode or production line? (numeric starting at 01 or AA?) R = die revision YM2164s: 58 05 83 C = hitachi