DS1243 Maxim Integrated Products, DS1243 Datasheet
DS1243
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DS1243 Summary of contents
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GENERAL DESCRIPTION The DS1254 is a fully nonvolatile static RAM (NV SRAM) (organized as 2M words by 8 bits) with built-in real-time clock. It has a self-contained lithium energy source and control circuitry that constantly monitors V tolerance condition. ...
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DETAILED DESCRIPTION The DS1254 is a fully nonvolatile static RAM (NV SRAM) (organized as 2M words by 8 bits) with built-in real-time clock. It has a self-contained lithium energy source and control circuitry that constantly monitors V tolerance condition. When ...
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RAM READ MODE The DS1254 executes a read cycle whenever WE is inactive (high) and CE is active (low). The unique address specified by the 21 address inputs (A0–A20) defines which of the 2MB of data accessed. ...
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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 OE pin or the WE pin. Cycles ...
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Figure 3. Phantom Clock Register Definition ...
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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 with logic high being PM. ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground Operating Temperature Range Storage Temperature Range Soldering Temperature Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and ...
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CAPACITANCE ° + PARAMETER Input Capacitance A18 Input Capacitance: A19 to A20 I/O Capacitance: DQ0 to DQ7 Output Capacitance ELECTRICAL CHARACTERISTICS ° = 5.0V ±10 ...
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AC ELECTRICAL CHARACTERISTICS ° 3.3V ±10 + PARAMETER Read Cycle Time Address Access Time OE to Output Valid CE to Output Valid Output Active Output High-Z from ...
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BATTERY WARNING TIMING ° 5.0V ±10 + PARAMETER Battery Test Cycle Battery Test Pulse Width Battery Test to BW Active Valid to BW Valid TEST CONDITIONS Output Load: ...
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Figure 5. Memory Write Cycle Timing, Write-Enable Controlled (Notes 10, 11, 12, and 13) ADDRESS CE WE DQ0–DQ7 Figure 6. Memory Write Cycle Timing, Chip-Enable Controlled (Notes 10, 11, 12, and 13) ADDRESS CE ...
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Figure 7. Read Cycle to Phantom Clock DQ0 Figure 8. Write Cycle to Phantom Clock DQ0 COE ...
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Figure 9. Power-Up/Power-Down Waveform Timing (Note 14 PF(max) V PF(min) V BAT Figure 10. Battery Warning Detection (Note BAT BATTERY TEST ACTIVE ...
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NOTES: 1) Voltage referenced to ground. 2) These parameters are sampled with a 50pF load and are not 100% tested open-drain output and, as such, cannot source current. An external pullup resistor should be connected to ...
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PACKAGE INFORMATION (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/DallasPackInfo.) PKG MIN IN 1.570 1.580 A MM 39.88 40.13 IN 1.570 1.580 B MM 39.88 ...
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PACKAGE INFORMATION (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/DallasPackInfo.) DS1254 with Attached DS3800 Battery Cap PKG MIN A IN 1.656 MM 42.06 B ...
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... The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas Semiconductor Corporation. ...