DS1243 Maxim, DS1243 Datasheet
DS1243
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DS1243 Summary of contents
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... NV SRAM with Phantom Clock PIN CONFIGURATION TOP VIEW RST A12 DQ0 DQ1 DQ2 GND PIN-PACKAGE 28 EDIP (0.720a DS1243Y DS1243Y A11 A10 DQ7 11 18 DQ6 ...
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... DESCRIPTION The DS1243Y 64K NV SRAM with Phantom Clock is a fully static nonvolatile RAM (organized as 8192 words by 8 bits) with a built-in real time clock. The DS1243Y has a self-contained lithium energy source and control circuitry, which constantly monitors V condition occurs, the lithium energy source is automatically switched on and write protection is unconditionally enabled to prevent corrupted data in both the memory and real time clock ...
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... RAM and disconnects the lithium energy source. Normal RAM operation can resume CC after V exceeds 4.5V. CC See “Conditions of Acceptability” at FRESHNESS SEAL Each DS1243Y is shipped from Maxim with its lithium energy source disconnected, insuring full energy capacity. When V is first applied at a level greater than V CC battery backup operation. (Write Enable) is inactive (high) and WE ...
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PHANTOM CLOCK OPERATION Communication with the Phantom Clock is established by pattern recognition on a serial bit stream of 64 bits which must be matched by executing 64 consecutive write cycles containing the proper data on DQ0. All accesses which ...
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PHANTOM CLOCK REGISTER DEFINITION Figure 1 NOTE: THE PATTERN RECOGNITION IN HEX IS C5, 3A, A3, 5C, C5, 3A, A3, 5C. THE ODDS OF THIS PATTERN BEING ACCIDENTALLY DUPLICATED AND CAUSING INADVERTENT ENTRY TO THE PHANTOM CLOCK IS LESS THAN ...
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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- 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 ...
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... Note: EDIP is wave or hand-soldered only. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. ...
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... Data Setup Time t DS Data Hold Time from 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 DS1243Y-120 UNITS NOTES MIN MAX 120 ns 120 120 ns 5 ...
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PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS (V = 4.5V to 5.5V 0°C to +70°C PARAMETER Read Cycle Time Access Time CE Access Time OE to Output Low Output Low Output High ...
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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 ...
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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. DS1243Y PAGES CHANGED ...