description the accutek ak532256w high density memory module is a cmos dynamic ram organized in 256k x 32 bit words. the module con - sists of eight standard 256 k x 4 drams in plastic soj packages. the assembly has eight drams mounted on the front side of a printed circuit board in a 72 pad leadless sim configuration. the operation of the ak532256w is identical to eight 256k x 4 drams. there are four cas lines and two ras lines. independent byte control is accomplished by four cas lines. each seperate cas line controls two 256 k x 4 drams to form an 8 bit byte. the bank of 32 bits is controlled by the two ras lines. a sixteen bit data path can be produced by connecting dq 1 to dq 17 ,dq 2 to dq 18 and alter - nately strobing ras 0 with ras 2 . features 262,144 x 32 bit organization 72 pin single in-line module multiple cas and ras lines allow x16 or x32 bit widths cas -before- ras refresh, ras -only refresh or hidden refresh operating free air temperature 0 o cto70 o c single 5 volt power supply 512 refresh cycles, 8msec power 2.00 watt max active (60ns) 1.78 watt max active (70 ns) 1.562 watt max active (80 ns) 44 mw max standby available in fast page mode, edo and static column mode versions available in leadless sim or leaded zip versions upward compatible with ak532512, AK5321024, ak5322048, ak5324096 and ak5328192 additional options available 512k x 32 version, ak532512 1 meg x 32 version, AK5321024 2 meg x 32 version, ak5322048 4 meg x 32 version, ak5324096 8 meg x 32 version, ak5328192 accutek microcircuit corporation ak532256w 262,144 word by 32 bit cmos dynamic random access memory + + + pin nomenclature a 0 -a 8 address inputs dq 1 -dq 32 data in/data out cas 0 - cas 3 column address strobe ras 0 , ras 2 row address strobe we write enable pd 1 -pd 4 presence detect vcc 5v supply vss ground nc no connect module options leadless sim: ak532256w leaded zip: ak532256wz pin assignment pin # symbol pin # symbol pin # symbol pin # symbol 1 vss 19 nc 37 nc 55 dq12 2 d1 20 dq5 38 nc 56 dq28 3 dq17 21 dq21 39 vss 57 dq13 4 dq2 22 dq6 40 cas 0 58 dq29 5 dq18 23 dq22 41 cas 2 59 vcc 6 dq3 24 dq7 42 cas 3 60 dq30 7 dq19 25 dq23 43 cas 1 61 dq14 8 dq4 26 dq8 44 ras 0 62 dq31 9 dq20 27 dq24 45 nc 63 dq15 10 vcc 28 a7 46 nc 64 dq32 11 nc 29 nc 47 we 65 dq16 12 a0 30 vcc 48 nc 66 nc 13 a1 31 a8 49 dq9 67 pd1 14 a2 32 nc 50 dq25 68 pd2 15 a3 33 nc 51 dq10 69 pd3 16 a4 34 ras 2 52 dq26 70 pd4 17 a5 35 nc 53 dq11 71 nc 18 a6 36 nc 54 dq27 72 vss presence detect - -60 -70 -80 pd1 vss vss vss pd2 nc nc nc pd3 nc vss nc pd4 nc nc vss
functional diagram mechanical dimensions accutek microcircuit corporation business center at newburyport 2 new pasture road, suite 1 newburyport, ma 01950-4054 phone: 978-465-6200 fax: 978-462-3396 email: sales@accutekmicro.com internet: www.accutekmicro.com 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. pre - liminary data sheets contain minimum and maximum limits based upon design objectives, which are subject to change upon full characterization over the specific operating conditions. + + c l c l c l + 1.000" max 0.200" max 0.425" 0.375" 0.250" c l 0.080" 0.125" 0.050" typ 4.250" 3.985" a0 - a8 9 ras0 we oe oe oe oe oe oe oe oe dq0 - dq4 dq4 - dq7 dq8 - dq11 dq12 - dq15 dq16 - dq19 dq20 - dq23 dq24 - dq27 dq28 - dq31 a0 - a8 a0 - a8 a0 - a8 a0 - a8 a0 - a8 a0 - a8 a0 - a8 a0 - a8 cas cas cas cas cas cas cas cas we we we we we we we we ras ras ras ras ras ras ras ras oe oe oe oe oe oe oe oe dq0 - dq3 dq0 - dq3 dq0 - dq3 dq0 - dq3 dq0 - dq3 dq0 - dq3 dq0 - dq3 dq0 - dq3 ras2 cas1 cas0 cas2 cas3
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