DS1244W-120 DALLAS [Dallas Semiconductor], DS1244W-120 Datasheet
DS1244W-120
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DS1244W-120 Summary of contents
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FEATURES § Real-time clock (RTC) keeps track of hundredths of seconds, minutes, hours, days, date of the month, months, and years § 32k SRAM directly replaces volatile static RAM or EEPROM § Embedded lithium energy ...
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... The part number for the Powercap is DS9034PCX. TYPICAL OPERATING CIRCUIT TEMP RANGE 0°C to +70°C * 0°C to +70°C 0°C to +70°C -40°C to +85°C * 0°C to +70°C * -40°C to +85° TOP MARK DS1244Y-70 DS1244YP-70 DS1244W-120 DS1244W-120IND DS1244WP-120 DS1244WP-120IND for an out-of-tolerance CC ...
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RAM READ MODE The DS1244 executes a read cycle whenever WE (write enable) is inactive (high) and CE (chip enable) is active (low). The unique address specified by the 15 address inputs (A0–A14) defines which of the 32,768 bytes of ...
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the first bit of the 64-bit comparison register. Next, 64 consecutive write cycles are executed using the and control of the ...
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Figure 1. PHANTOM CLOCK REGISTER DEFINITION 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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Figure 2. PHANTOM CLOCK REGISTER DEFINITION 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 DS1244 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 DS1244 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 Soldering Temperature Range OPERATING RANGE RANGE TEMP RANGE Commercial 0°C to +70°C Industrial -40°C to +85°C *This is a stress rating only and functional operation of ...
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DC ELECTRICAL CHARACTERISTICS PARAMETER Input Leakage Current I/O Leakage Current CE ³ V ≤ Output Current at 2.4V Output Current at 0.4V Standby Current CE = 2.2V Standby Current 0.5V CC Operating Current ...
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PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS PARAMETER Read Cycle Time Access Time CE Access Time OE to Output Low Output Low Output High Output High-Z OE Read Recovery Write Cycle Time Write Pulse Width Write ...
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... CE to Output Low Output High Output High-Z OE Read Recovery Write Cycle Time Write Pulse Width Write Recovery Data Setup Time Data Hold Time Pulse Width CE Pulse Width RESET DS1244W-120 SYMBOL MIN t 120 RC t ACC COE t OD ...
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POWER-DOWN/POWER-UP TIMING PARAMETER at V before Power-Down Slew from PF(MAX PF(MIN Slew from PF(MAX PF(MIN ...
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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 ...
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POWER-DOWN/POWER-UP CONDITION, 5V POWER-DOWN/POWER-UP CONDITION, 3. ...
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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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DS1244P WITH DS9034PCX ATTACHED PKG DIM COMPONENTS AND PLACEMENT MIGHT VARY FROM EACH DEVICE TYPE INCHES MIN NOM MAX A 0.920 0.925 0.930 B 0.955 0.960 0.965 C 0.240 0.245 0.250 D 0.052 0.055 0.058 E 0.048 ...
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RECOMMENDED POWERCAP MODULE LAND PATTERN Note: Dallas Semiconductor recommends that PowerCap module bases experience one pass through solder reflow oriented with the label side up (“live-bug”). Hand soldering and touch-up: Do not touch or apply the soldering iron to leads ...