Next Generation 19 MM Recorder Technology D. Morgan, T. Yoshida Sony Electronics Inc. 3300 Zanker Rd, San Jose, CA Tel: (408) 955-4925, Fax: (408) 955-5555 email: don_morgan@sdc.sel.sony.com April 21, 1998 SONY 1
Objective of Research Study Search for a path to higher performance Data Rate / Capacity Recorder / Format Examine maintaining some compatibility with ID-1 format April 21, 1998 SONY 2
Target Specifications DIR-1000H DIR-X DIR-XX User Data Transfer Rate 512 Mbps 1024 Mbps 2048 Mbps Storage Capacity L 100 GByte 200 Gbyte 456 GByte Media Co-oxide 16 µ m Co-oxide 16 µ m Metal 13 µ m Rec Data Rate/ch 88 Mbps 88 Mbps 176 Mbps Rec Hds / Proc ch 16/8ch 32/16ch 32/16ch Shortest Wavelength 0.89 µ m 0.89 µ m 0.49 µ m Track Pitch 45 µ m 22.5 µ m 22.5 µ m Writing Speed 39.5 m/sec 39.5 m/sec 42.8 m/sec Tape Speed 847.5mm/sec 847.5mm/sec 918.0mm/sec Scanner Rotation 110 rps- 110 rps 120 rps Record Time/L-Cassette 26 min 26 min 29 min April 21, 1998 SONY 3
ID-1 Review Track Set 5J=HJ BJH=? IAJ ) J = J E J H =? 5J=HJ BJH=? IAJ 0 A=@ JE 6 = F A J E + J H J H =? ) J = J E J H =? April 21, 1998 SONY 4
ID-1 Review Helical Track Dimensions ) J= JE JH=?, EH A? J E B D A = @ J E 45 µ "#µ %, EH A? J E B J = F A J E + J H J H =? 6 E A? @ A J H =? 4 A B A H A? A A @ C A April 21, 1998 SONY 5
ID-1 Review Track Straightness "#µ µ #µ 4 A B A H A? A A @ C A A A A! A " A # A $ 6 = F A A @ C A April 21, 1998 SONY 6
ID-1 Review Cross Track Straightness of DIR-1000 0.1µm Units 100 75 50 25 0-25 -50-75 Line 1 Line 2 Line 3-100 1 16 32 48 64 80 96 11 2 12 8 14 4 16 0 17 6 19 2 20 8 22 4 24 0 25 6 27 2 30 4 32 0 33 6 35 2 36 8 Track Number April 21, 1998 SONY 7
ID-1 Review User data - 36,108 Bytes/Track C1, C2 ECC Interleaved within the Track Track Set ( 144,432 Bytes ) uniquely identified by 32 bit TSID on Control Track and by 22 bit plus track position ID in each Helical Track April 21, 1998 SONY 8
DD-1 Review User Data - 32,768 Bytes/Track C3 ECC Interleaved across Track Set April 21, 1998 SONY 9
DIR-1000 to DIR-1000H DIR-1000 DIR-1000H Record Data Rate / ch 88 Mbps 88 Mbps Number of Heads Rec: 8 / PB: 8 Rec: 16 / PB: 16 Number of Rotary Transformer Channels Rec: 8 / PB: 8 Rec: 8 / PB: 8 Drum Rotation 110 rps 110 rps Tape Speed 423.6 mm/s 847.2 mm/s April 21, 1998 SONY 10
Scanner Head Drum April 21, 1998 SONY 11
DIR-1000H Head switching Lower Drum Scanner Scanner Upper Drum REC Head MOS Relay Tape PB Head Pre Amp Rec Amp REC BOARD EQ BOARD (180 opposite) Control SIG Power Rotary Timing GEN Timing DEC 5V AC GEN PD BOARD April 21,1998 SONY 12
Noise Performance 0-10 -20 DIR-1000 Sony SD-1 ƒé O D W X (RBW 100K) Rec Head (Ferrite) :45um PB Head (Ferrite) :45um 0-10 -20 DIR-1000H Sony SD-1 (RBW 100K) ƒé OD W X Rec Head (Ferrite) :45ƒÊ m PB Head (Amorphous) :30ƒÊ m output (db) -30-40 -50-60 -70-80 -90 Pre Amp noise 0 10 20 30 40 50 60 Frequencv (MHz) Output (db) -30-40 -50-60 -70-80 Pre Amp noise -90 0 10 20 30 40 50 60 Frequency (MHz) April 21,1998 SONY 13
Recording One Gigabit/sec, 2X DIR-X is possible by doubling the number of channels: 32 record heads driven by 16 channels of electronics, reducing the track width and pitch to 22.5 µm Several issues must be considered How much compatibility with ID-1 format? Recording DIR-X Track Set defined as 4 or 8 helical tracks? ECC block size? April 21, 1998 SONY 14
Compatibility with ID-1 Format Reading ID-1 format with narrow track heads is possible. If writing an ID-1 footprint is required for 1X recording there are two possibilities: One method - have two sets of record heads (45 µm, 22.5 µm) The other method - overwrite previously written wide tracks at half the tape speed which results in narrow tracks This later case may require changing the channel coding from 8/9 to something with less low frequency content. April 21, 1998 SONY 15
Overwrite Method 5J=HJ BJH=? IAJ ) J = J E J H =? 0 A=@ JE # µ 6 = F A J E + J H J H =? ) J = J E J H =? April 21, 1998 SONY 16
Recording DIR-X Track Set defined as 4 or 8 helical tracks? If 4 tracks Longitudinal TSID must be written at double density. This is being studied. The parameters of ID-1 and DD-1 apply. If 8 tracks Helical track ID must be redefined in the track identification bits. The TSID represents twice the data size or 288,864 bytes of user data. April 21, 1998 SONY 17
ECC block size? The narrow tracks of the 2X recording theoretically degrades the signal to noise ratio by 3 db and thus the raw random errors by more than 3 orders of magnitude. It may be desirable to increase the ECC block size such that C2 is interleaved over entire Track Set (4 or 8 tracks) to improved the performance of the ECC. April 21, 1998 SONY 18
Advances in head technology Reference: IEEE Transactions on Magnetics, November 1994 H. Ohmori, et al, A Thin Film Head for HD-VCRs The key advantages are: high efficiency head MIG allows recording MP tape at higher data-rates Amorphous PB heads - increased output from MP tape small chip size -localized free air flux spray small rubbing surface surrounded by non-magnetic ceramic allows for new low-noise Pre-amp design more head chips around the drum higher frequency capability allow for higher channel data-rates April 21, 1998 SONY 19
E-TF Heads One difficulty with E-TF heads is that gap widths are limited to between 20-25µm. The reasons for this are economical production difficulty in producing uniform layers. 45 µm track width recording not possible with E-TF heads. April 21, 1998 SONY 20
Embedded Thin Film Heads April 21, 1998 SONY 21
Multiple Gap Head Tests April 21, 1998 SONY 22
Contact Area / Tip Projection Head-1 Head-2 Y GL=900um 20nm 60nm 100nm Rx=10.5mm,Ry=2mm,P-40um,T=30gf 20nm 60nm 100nm Rx=15mm,Ry=2.5mm,P-45um,T=30gf X Longitudinal radius,rx(mm) 20 18 16 14 12 30 Good contact area 35 40 45 50 Head protrusion,p(um) 20nm 60nm 100nm 1.8mm 0.2mm Œ» s ƒw ƒb ƒh DIR 1000H Head-3 Rx=15mm,Ry=4mm,P-45um,T=30gf 0.25mm Rx=8mm 2mm Magnetic core Ferrit Rx=15mm Ceramic Magnetic core Thin film coil April 21,1998 SONY 23
The Ultimate Possibility, 2 Gigabit/sec, 4X DIR-XX achieved by doubling the channel data-rate over that of DIR-X MP media allows higher density recording by 2x Shortest wave length held to 0.49 µm by slightly increasing the writing speed, tape speed and scanner rotation (see table). Record time ( L-Cassette) is extended to 29 minutes by using 13 mm tape thickness. April 21, 1998 SONY 24
Multigap Heads on Drum April 21, 1998 SONY 25
Noise Performance 0-10 -20 DIR-1000 DIR-1000H DIR-XX Sony SD-1 ƒé OD W X (RBW 100K) Rec Head (Ferrite) :45um PB Head (Ferrite) :45um (RBW 100K) 0-10 -20 Sony SD-1 ƒé OD W X Rec Head (Ferrite) :45ƒÊ m PB Head (Amorphous) :30ƒÊ m 0-10 -20 Sony HD Tape (RBW 100K) ƒé OD S X Rec Head (Ferrite.HM) :20ƒÊ m PB Head (Amorphous) :30ƒÊ m output -30-40 -50-60 Output (db) -30-40 -50-60 Output (db) -30-40 -50-60 -70-70 -70 (db) -80 Pre Amp noise -90 0 10 20 30 40 50 60 Frequencv (MHz) -80 Pre Amp noise -90 0 10 20 30 40 50 60 Frequency (MHz) -80 Pre Amp noise -90 0 10 20 30 40 50 60 Frequency (MHz) April 21,1998 SONY 26
The Challenge Is it necessary for the new high performance implementation of DIR-X to have foreward compatibility with ID-1 format recorded tapes? If the answer is no, manufacturers can focus on implementing a new format for optimum performance, first at 1 Gbps, with the next generation implementation at 2 Gbps. The enabling technologies are within our grasp to accomplish these challenging projects. April 21, 1998 SONY 27