Rainbow-electronics DS1251Y Manual do Utilizador Página 1

1 of 22 112801FEATURES§ Real-time clock keeps track of hundredths ofseconds, minutes, hours, days, date of themonth, months, and years§ 512k x 8 NV

DS1251/DS1251P10 of 22MEMORY AC ELECTRICAL CHARACTERISTICS Over the operating range (5V)DS1251Y-70PARAMETER SYMBOLMIN MAXUNITS NOTESRead Cycle Time tR

DS1251/DS1251P11 of 22PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICSOver the operating range (5V)PARAMETER SYMBOL MIN TYP MAX UNITS NOTESRead Cycle Time

DS1251/DS1251P12 of 22MEMORY AC ELECTRICAL CHARACTERISTICSOver the operating range (3.3V)DS1251W-120PARAMETER SYMBOLMIN MAXUNITS NOTESRead Cycle Time

DS1251/DS1251P13 of 22POWER-DOWN/POWER-UP TIMING Over the operating range (3.3V)PARAMETER SYMBOL MIN TYP MAX UNITS NOTESCE at VIH before Power-DowntP

DS1251/DS1251P14 of 22MEMORY READ CYCLE (Note 1)MEMORY WRITE CYCLE 1 (Notes 2, 6, and 7)

DS1251/DS1251P15 of 22MEMORY WRITE CYCLE 2 (Notes 2 and 8)RESET FOR PHANTOM CLOCKREAD CYCLE TO PHANTOM CLOCK

DS1251/DS1251P16 of 22WRITE CYCLE TO PHANTOM CLOCKPOWER-DOWN/POWER-UP CONDITION (5V)

DS1251/DS1251P17 of 22POWER-DOWN/POWER-UP CONDITION (3.3V)

DS1251/DS1251P18 of 22AC TEST CONDITIONSOutput Load: 50pF + 1TTL GateInput Pulse Levels: 0V to 3VTiming Measurement Reference LevelsInput: 1.5VOu

DS1251/DS1251P19 of 22DS1251 4096k NV SRAM WITH PHANTOM CLOCKKG 32-PINDIM MIN MAXA IN.MM1.68042.671.74044.20B IN.MM0.71518.160.74018.80C IN.MM0.335

DS1251/DS1251P2 of 22ORDERING INFORMATIONDS1251YP–XXXY (5V)- IND Industrial - 70 70ns access blank 32-Pin DIP Module P 34-Pin Pow

DS1251/DS1251P20 of 22DS1251PPKG INCHESDIM MIN NOM MAXA0.920 0.925 0.930B0.980 0.985 0.990C- - 0.080D0.052 0.055 0.058E0.048 0.050 0.052F0.015 0.020 0

DS1251/DS1251P21 of 22DS1251P WITH DS9034PCX ATTACHEDPKG INCHESDIM MIN NOM MAXA0.920 0.925 0.930B0.955 0.960 0.965C0.240 0.245 0.250D0.052 0.055 0.058

DS1251/DS1251P22 of 22RECOMMENDED POWERCAP MODULE LAND PATTERNPKG INCHESDIM MIN NOM MAXA- 1.050 -B- 0.826 -C- 0.050 -D- 0.030 -E- 0.112 -

DS1251/DS1251P3 of 22RAM READ MODEThe DS1251 executes a read cycle whenever WE (write enable) is inactive (high) and CE (chip enable) isactive (lo

DS1251/DS1251P4 of 22CE and OE control of the phantom clock starts the pattern recognition sequence by moving a pointer tothe first bit of the 64-b

DS1251/DS1251P5 of 22PHANTOM CLOCK REGISTER DEFINITION Figure 1Note: The pattern recognition in Hex is C5, 3A, A3, 5C, C5, 3A, A3, 5C. The odds of thi

DS1251/DS1251P6 of 22PHANTOM CLOCK REGISTER DEFINITION Figure 2AM/PM/12/24 MODEBit 7 of the hours register is defined as the 12-hour or 24-hour mode-s

DS1251/DS1251P7 of 22BATTERY LONGEVITYThe DS1251 has a lithium power source that is designed to provide energy for clock activity, and clockand RAM da

DS1251/DS1251P8 of 22ABSOLUTE MAXIMUM RATINGS*Voltage Range on Any Pin Relative to Ground -0.3V to +6.0VSoldering Temperature Range +260°C for 10 sec

DS1251/DS1251P9 of 22DC ELECTRICAL CHARACTERISTICS Over the operating range (5V)PARAMETER SYMBOL MIN TYP MAX UNITS NOTESInput Leakag