DS1251 Maxim, DS1251 Datasheet
DS1251
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DS1251 Summary of contents
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... A11 A10 DQ7 13 20 DQ6 14 19 DQ5 15 18 DQ4 17 16 DQ3 740-Mil Flush A18 34 DS1251P 33 A17 32 A14 31 A13 30 A12 A11 29 28 A10 GND BAT 19 A1 ...
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... 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. PIN DESCRIPTION PIN NAME ...
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... DESCRIPTION The DS1251 4096K NV SRAM with Phantom Clock is a fully static nonvolatile RAM (organized as 512K words by 8 bits) with a built-in real-time clock. The DS1251Y has a self-contained lithium energy source and control circuitry, which constantly monitors V a condition occurs, the lithium energy source is automatically switched on and write protection is unconditionally enabled to prevent garbled data in both the memory and real-time clock ...
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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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... V CLOCK ACCURACY (DIP MODULE) The DS1251 is guaranteed to keep time accuracy to within ±1 minute per month at +25°C. The clock is calibrated at the factory by Maxim using special calibration nonvolatile tuning elements. The DS1251 does not require additional calibration and temperature deviations will have a negligible effect in most applications ...
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... Soldering Temperature (reflow, PowerCap .+260°C This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time can affect reliability. ...
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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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... Output High-Z from Deselection Output Hold from Address Change Write Cycle Time Write Pulse Width Address Setup Time Write Recovery Time Output High-Z from WE Output Active from WE Data Setup Time Data Hold Time from WE DS1251Y-70 SYMBOL MIN ACC ...
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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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... In addition, for the PowerCap: 1) Maxim recommends that PowerCap Module bases experience one pass through solder reflow oriented with the label side up (“live-bug”). 2) Hand soldering and touch-up: Do not touch or apply the soldering iron to leads for more than three seconds. − ...
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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 drawing pertains to the package regardless of RoHS status. ...
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... © 2011 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. DS1251/DS1251P PAGES CHANGED ...