DS1251WP-C02 Maxim Integrated, DS1251WP-C02 Datasheet

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FEATURES  Real-Time Clock Keeps Track of Hundredths Of Seconds, Minutes, Hours, Days, Date of the Month, Months, and Years  512K SRAM Directly Replaces Volatile Static RAM or EEPROM  Embedded Lithium Energy Cell Maintains Calendar ...

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... ORDERING INFORMATION PART TEMP RANGE DS1251W-120+ 0°C to +70°C DS1251W-120IND+ -40°C to +85°C DS1251WP-120+ 0°C to +70°C DS1251WP-120IND+ -40°C to +85°C DS1251Y-70+ 0°C to +70°C DS1251YP-70+ 0°C to +70°C DS1251YP-70IND+ -40°C to +85°C + Denotes a lead(Pb)-free/RoHS-compliant package. *DS9034PCX+ or DS9034I-PCX+ (PowerCap) required. Must be ordered separately. ...

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PIN DESCRIPTION (continued) PIN NAME EDIP PowerCap — GND DESCRIPTION The DS1251 4096K NV SRAM with Phantom Clock is a fully static nonvolatile ...

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The WR write cycles to avoid bus contention. However, if the output bus has been enabled ( then will disable the outputs ...

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The next 64 cycles will cause the phantom clock to either receive or transmit data on DQ0, depending on the level of the locations outside the memory block can be interleaved with recognition sequence ...

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PHANTOM CLOCK REGISTER DEFINITION Figure 2 AM/PM/12/24 MODE Bit 7 of the hours register is defined as the 12-hour or 24-hour mode-select bit. When high, the 12-hour mode is selected. In the 12-hour mode, bit 5 is the AM/PM bit ...

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BATTERY LONGEVITY The DS1251 has a lithium power source that is designed to provide energy for clock activity, and clock and RAM data retention when the V is sufficient to power the DS1251 continuously for the life of the equipment ...

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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground Storage Temperature Range EDIP . . . . . . . . . . . . . . . . . . . . . . . . . ...

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DC ELECTRICAL CHARACTERISTICS (T = Over the operating range.) (5V ARAMETER 0 B Input Leakage Current I/O Leakage Current CE ≥ V ≤ Output Current at 2.4V Output Current at 0.4V Standby Current CE = ...

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MEMORY AC ELECTRICAL CHARACTERISTICS (T = Over the operating range.) (5V ARAMETER 3 B Read Cycle Time Access Time OE to Output Valid CE to Output Valid Output Active Output High-Z from Deselection Output ...

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PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS (T = Over the operating range.) (5V ARAMETER Read Cycle Time CE Access Time OE Access Time CE to Output Low Output Low Output High-Z OE ...

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MEMORY AC ELECTRICAL CHARACTERISTICS (T = Over the operating range.) (3.3V) A PARAMETER Read Cycle Time Access Time OE to Output Valid CE to Output Valid Output Active Output High-Z from Deselection Output Hold from Address ...

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POWER-DOWN/POWER-UP TIMING (T = Over the operating range.) (3.3V ARAMETER before Power-Down IH V Slew from PF(MAX PF(MIN Slew from V to ...

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MEMORY READ CYCLE (Note 1) MEMORY WRITE CYCLE 1 (Notes 2, 6, and ...

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MEMORY WRITE CYCLE 2 (Notes 2 and 8) RESET FOR PHANTOM CLOCK READ CYCLE TO PHANTOM CLOCK ...

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WRITE CYCLE TO PHANTOM CLOCK POWER-DOWN/POWER-UP CONDITION (5V ...

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POWER-DOWN/POWER-UP CONDITION (3.3V ...

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AC TEST CONDITIONS Output Load: 50pF + 1TTL Gate Input Pulse Levels Timing Measurement Reference Levels Input: 1.5V Output: 1.5V Input Pulse Rise and Fall Times: 5ns NOTES high for a read cycle. 2) ...

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PACKAGE INFORMATION For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the ...

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... © 2011 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. DS1251/DS1251P PAGES CHANGED ...