Accutek Microcircuit Corporation AK58256AG / AK58256AS 262,144 x 8 bit CMOS Dynamic Random Access Memory DESCRIPTION Front View The Accutek AK58256AG/AS high density memory module is a random access memory organized in 256K x 8 bit words. The assembly consists of two 256K x 4 DRAMs in surface mount packages mounted to the front side of a printed circuit board. The module can be configured as a leadless 30 pad SIM or a leaded 30 pin SIP. This packaging approach provides a better than 6 to 1 density increase over standard DIP packaging. 30-Pin SIM + + 30 1 30-Pin SIP The operation of the AK58256 is identical to two 256K x 4 DRAMs. The data input/output is brought out separately for each 256K x 4 device, with common RAS, CAS and WE control. The OE pins are tied to Vss which dictates the use of early-write cycles to prevent contention of D and Q. Since the Write-Enable (WE) signal must always go low before CAS in a write cycle, Read-Write and Read-Modify-Write operation is not possible. + + 1 FEATURES · 262,144 x 8 bit organization · Optional 30 Pad leadless SIM (Single In-Line Module) or 30 Pin leaded SIP (Single In-Line Package) · JEDEC standard pinout · Common CAS, RAS and WE control for eight DQ lines · Separate CAS control for one separate pair of D and Q lines · 1024 refresh cycles/16ms, A0 to A8 · Power: .99 Watt Max Active (60 nS) .88 Watt Max Active (70 nS) .77 Watt Max Active (80 nS) .65 Watt Max Active (100 nS) 11 mWatt standby (max) · Operating free air temperature: 00 to 700C · Upward compatible with AK581024, AK584096 and AK5816384 · Functionally and Pin compatible with AK48256 · Available with access times of 60 to 100 nS PIN NOMENCLATURE PIN ASSIGNMENT FUNCTIONAL DIAGRAM PIN # SYMBOL PIN # SYMBOL 1 Vcc 16 DQ5 Address Inputs 2 CAS 17 A8 CAS Column Address Strobe 3 DQ1 18 NC RAS Row Address Strobe 4 A0 19 NC 5 A1 20 DQ6 WE Write Enable 6 DQ2 21 WE Vcc 5v Supply 7 A2 22 Vss Vss Ground 8 A3 23 DQ7 9 Vss 24 NC NC No Connect 10 DQ3 25 DQ8 11 A4 26 NC MODULE OPTIONS 12 A5 27 RAS 13 DQ4 28 NC Leadless SIM: AK58256AS 14 A6 29 NC 15 A7 30 Vcc DQ1 - DQ8 Data In / Data Out A0 - A8 Leaded SIP: AK58256AG A0 - A8 + RAS + CAS + WE + DQ1 + DQ2 + DQ3 + DQ4 + A0 - A8 * RAS * CAS * WE * DQ1 * DQ2 * DQ3 * DQ4 OE * + + + + A0 - A8 * RAS * CAS * WE * DQ1 * DQ2 * DQ3 * DQ4 OE * DQ5 DQ6 DQ7 DQ8 EXAMPLES: ORDERING INFORMATION AK58256ASP-60 PART NUMBER CODING INTERPRETATION Position 1 2 3 4 5 6 7 8 AK58256AGK-70 256K x 8, Dynamic RAM, Leaded SIP, Static Column Mode Commercial, 70 nSEC AccessTime MECHANICAL DIMENSIONS Inches 0.410 0.390 1 + 0.100 T.P. 3.510 3.490 3.245 3.225 3.110 3.090 30 + + 0.100 TYP The numbers and coding on this page do not include all variations available, but are shown as examples of the most widely used variations. Contact Accutek if other information is required. 0.200" MAX 0.053 0.047 ACCUTEK MICROCIRCUIT CORPORATION BUSINESS CENTER at NEWBURYPORT 2 NEW PASTURE ROAD, SUITE 1 NEWBURYPORT, MA 01950-4054 VOICE: 978-465-6200 FAX: 978-462-3396 Email: [email protected] Internet: www.accutekmicro.com 0.260 0.240 0.085 0.075 0.325 0.275 + 1 0.024 0.016 Product AK = Accutek Memory Type 4 = Dynamic RAM 5 = CMOS Dynamic RAM 6 = Static RAM Organization/Word Width 1 = by 1 16 = by 16 4 = by 4 32 = by 32 8 = by 8 36 = by 36 9 = by 9 Size/Bits Depth 64 = 64K 4096 = 4 MEG 256 = 256K 8192 = 8 MEG 1024 = 1 MEG 16384 = 16 MEG Package Type G = Single In-Line Package (SIP) S = Single In-Line Module (SIM) D = Dual In-Line Package (DIP) W = .050 inch Pitch Edge Connect Z = Zig-Zag In-Line Package (ZIP) Special Designation P = Page Mode N = Nibble Mode K = Static Column Mode W = Write Per Bit Mode V = Video Ram Separator - = Commercial 00C to +700C M = Military Equivalent Screened (-550C to +1250C) I = Industrial Temperature Tested (-450C to +850C) X = Burned In Speed (first two significant digits) DRAMS SRAMS 60 = 60 nS 8 = 8 nS 70 = 70 nS 12 = 12 nS 80 = 80 nS 15 = 15 nS 10 = 100 nS 20 = 20 nS 12 = 120 nS 70 = 70 nS 15 = 150 nS 85 = 85 nS 256K x 8, Dynamic RAM, Leadless SIM, Page Mode, Commercial, 60 nSEC Access Time 0.100 T.P. 8 4 0.505 0.495 7 3 0.100 TYP 6 2 0.515 0.505 5 1 Accutek reserves the right to make changes in specifications at any time and without notice. Accutek does not assume any responsibility for the use of any circuitry described; no circuit patent licenses are implied. Preliminary data sheets contain minimum and maximum limits based upon design objectives, which are subject to change upon full characterization over the specific operating conditions.