? semiconductor 1/9 MSM6684B general description MSM6684B is a serial register organized as 4,194,304 words x one bit, characterized by medium- speed, low power consumption operation. this device has a built-in internal address generation circuit allowing continuous serial read/write operation by external clock input. read/write operation causes the internal address to be incremented automatically by +1. external address input enables addressing in units of 1024 words. furthermore, a refresh timer and a refresh address counter are installed, which makes an external refresh circuit unnecessary. in addition, this configuration allows lower power consumption. the device is packaged in 26/20-pin soj having a width of 300 mil. it is well adapted for storing much data by means of a battery backup. its combination with our recording and playback lsi enables the easy implementation of a solid recording and playback system. features ? configuration 4,194,304 x 1 bit ? serial access operation serial access time : 1.5 m s serial read/write time : 2.5 m s ? low current drain 150 m a max. (v cc = 4 v with data stored and under standard conditions) ? refresh operation a self-refresh function is supported. ? wide operation voltage range single 3.5 to 5.5 v ? addressing units of 1024 words ? process 0.45 m m double well cmos process ? package : 26/20-pin plastic soj (soj26/20-p-300-1.27) (product name : MSM6684Bjs) ? semiconductor MSM6684B 4,194,304-word x 1-bit serial register e2d0035-27-42 this version: jan. 1998 previous version: may. 1997
? semiconductor 2/9 MSM6684B block diagram refresh timer refresh address counter row address counter row address register timing generator tas sad sas rwck address multiplexer row decoder 4, 194, 304 data register column decoder column address counter write clock generator i/o control din we dout
? semiconductor 3/9 MSM6684B pin configuration (top view) test rwck nc test test v ss nc din test test 1 2 3 4 5 9 10 11 12 13 v cc 26 test 25 test 24 sad 23 sas 22 nc 14 dout 15 we 16 cs 17 tas 18 nc : no connection 26/20-pin plastic soj pin description symbol description test test input test test input rwck read/write clock din data input v ss ground (0 v) dout data output we write enable cs chip select tas transfer address strobe sas serial address strobe sad serial address data v cc power supply (5 v) pin 25 1, 4, 5, 9, 10, 24 2 11 13 15 16 17 18 22 23 26 note : all test pins are to be connected to the power supply. the test pin is to be referenced to the ground level.
? semiconductor 4/9 MSM6684B absolute maximum ratings parameter symbol min. typ. max. unit supply voltage v cc 3.5 4.5 5.5 supply voltage 0 0 0 "h" input voltage v cc C 0.5 v cc v cc + 0.2 "l" input voltage C0.2 0 +0.5 v v v v v ss v ih v il (ta=0 to 70c) electrical characteristics dc characteristics parameter symbol condition rating unit pin voltage v t against v ss at ta = 25 c C1.0 to +7.0 v output short-circuit current ta = 25 c 50 ma power dissipation 1 w operating temperature 0 to 70 c storage temperature C55 to +150 c i os p d t op t stg ta = 25 c recommended operating conditions parameter symbol condition min. max. unit "h" output voltage v oh i oh =C0.5 ma v cc C 0.5 v "l" output voltage i ol =0.5 ma 0.4 v input leakage current i il v i =0 v to v cc C1 +1 m a output leakage current v o =0 v to v cc C1 +1 m a supply current (operation) v cc =4 v, t rwc =1 m s 20 ma supply current (standby) v cc =4 v 150 m a v ol i ol i cc1 i cc2 (v cc =3.5 v to 5.5 v, ta=0 to 70c)
? semiconductor 5/9 MSM6684B ac characteristics parameter symbol min. max. units read/write cycle time t rwc 2,500 ns access time t acc 1,500 ns output turn-off delay time t off 050ns i/o signal rise time t t 350ns rwck pre-charge time t rwp 1,000 ns sas cycle time t rw 1,500 10,000 ns sas pre-charge time t ssc 100 ns sas pulse width t sap 50 ns address setup time t sas 50 ns adress hold time t as 0ns tas setup time t ah 50 ns tas . rwck setup time t ats 50 ns tas pulse width t trs 50 ns read instruction setup time t tas 50 ns read instruction hold time t rrs 0ns write instruction setup time t rrh 250 ns write instruction hold time t wrs 0ns write instruction pulse width t wrh 50 ns we . rwck read time t wp 50 ns data setup time t rwl 50 ns data hold time t ds 0ns rwck . we delay time t dh 50 ns t rwd 50 ns rwck pulse time (v cc =3.5 v to 5.5 v, ta=0 to 70c)
? semiconductor 6/9 MSM6684B timing diagram read/write and read/modify/write cycles cs rwck sas sad tas we din dout t trs t rw t rwp t rwc t ssc t sap t sas t ah t as a0 a1 a12 n n+1 n+1 n+2 t acc t off t ds t dh t ds t dh t wrh t wrs t wp t rwd t rrh t rrs t tas t ats t rwl
? semiconductor 7/9 MSM6684B pin functions and operating modes ? serial address input (sad) pin used to enter start address for reading/writing. an address can be specified in units of 1024 words. 1024 words of address data can be entered through the pin as 13 bits (a0 to a12) of serial data. the 13th bit must be a12 as a dummy address, however. the a12 input level must be either "h" or "l". ? serial address strobe ( sas ) this is a clock pin for latching serial address data into an internal register. ? address transfer strobe ( tas ) this is an input pin for loading the internal address counter with serial address data latched in the address register. ? read/write clock ( rwck ) this is a clock input pin for reading and writing information in the data register. the trailing edge of rwck triggers off internal operation. in the reading mode, information in the data register is output to the dout pin. in the writing mode, the data register is loaded with din information. at the leading edge of rwck, the internal address counter is incremented automatically by +1. ? write enable ( we ) this is an input pin for selecting the read mode, the write mode, or the read-modify-write mode. when we is "h", the read mode is set up and, when we is "l", the write mode is set up. when the level is lowered from "h" to "l" with rwck active, the read-modify-write mode is set up. ? data input (din) this is a pin for entering write data. information on the data input pin is latched when the trailing edge of rwck is encountered in the write mode and that of we is encountered in the read/modify mode. ? data output (dout) the data output pin always provides high impedance as long as rwck or cs is kept at "h". when "h" or "l" information is read, the output pin set at "h" or "l", and information read until rwck returns to "h" is held. in the early write mode, the output pin is maintained at high impedance, so that, connect of din and dout enables "i/o common operation". ? chip selection ( cs ) this is an input pin for disabling all input pins. this pin allows the use of two or more MSM6684B devices with data input and output pins connected in parallel. ? test (test, test ) the test pin must always be fixed at "l" and the test pin at "h".
? semiconductor 8/9 MSM6684B notes on power-up MSM6684B has built-in board bias generation and inner power supply circuits. thus, energization must be followed by a pause period of 1 ms or more for internal circuit stabilization. furthermore, the test pin must be brought "l" concurrently with or prior to v cc , and all clock input pins and test pins must be brought "h" concurrently with or prior to v cc . to achieve proper operation of internal circuits, the initial pause above must be followed by minimum ten dummy read cycles with rwck . notes on supply voltage variation when using MSM6684B, take precautions so that the supply voltage does not vary over one volt within a period of 1,000 m s or less in the active state.
? semiconductor 9/9 MSM6684B (unit : mm) package dimensions notes for mounting the surface mount type package the sop, qfp, tsop, soj, qfj (plcc), shp and bga are surface mount type packages, which are very susceptible to heat in reflow mounting and humidity absorbed in storage. therefore, before you perform reflow mounting, contact okis responsible sales person for the product name, package name, pin number, package code and desired mounting conditions (reflow method, temperature and times). soj26/20-p-300-1.27 package material lead frame material pin treatment solder plate thickness package weight (g) epoxy resin 42 alloy solder plating 5 m m or more 0.80 typ. mirror finish
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