DS1744-70+ Dallas Semiconductor, DS1744-70+ Datasheet
DS1744-70+
Specifications of DS1744-70+
Related parts for DS1744-70+
DS1744-70+ Summary of contents
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... GND DS1744/DS1744P A14 CC DS1744 A12 3 26 A13 A11 A10 DQ7 11 18 DQ0 DQ6 12 17 DQ1 DQ5 13 16 DQ2 DQ4 14 15 GND DQ3 EDIP DS1744P GND BAT PowerCap MODULE BOARD (Uses DS9034PCX PowerCap) REV: 042506 N.C. N.C. A14 A13 A12 A11 A10 ...
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PIN DESCRIPTION PIN NAME EDIP PowerCap 1 32 A14 2 30 A12 A10 23 ...
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... ORDERING INFORMATION VOLTAGE PART (V) DS1744-70 5.0 DS1744-70+ 5.0 DS1744-70IND 5.0 DS1744-100+ 5.0 DS1744W-120 3.3 DS1744W-120+ 3.3 DS1744W-120IND 3.3 DS1744P-70 5.0 DS1744P-70+ 5.0 DS1744P-70IND 5.0 DS1744P-100+ 5.0 DS1744WP-120 3.3 DS1744WP-120+ 3.3 DS1744WP-120IND 3.3 + Denotes a lead-free/RoHS-compliant device. *DS9034-PCX, DS9034I-PCX, DS9034-PCX+ required (must be ordered separately). ...
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... CLOCK OPERATIONS—READING THE CLOCK While the double-buffered register structure reduces the chance of reading incorrect data, internal updates to the DS1744 clock registers should be halted before clock data is read to prevent reading of data in transition. However, halting the internal clock register updating process does not affect clock accuracy. ...
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... As shown in Table 2, bit 7 of the century register is the write bit. Setting the write bit like the read bit, halts updates to the DS1744 registers. The user can then load them with the correct day, date, and time data in 24-hour BCD format. Resetting the write bit then transfers those values to the actual clock counters and allows normal operation to resume ...
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... WRITING DATA TO RAM OR CLOCK The DS1744 is in the write mode whenever WE and CE are in their active state. The start of a write is referenced to the latter occurring transition The addresses must be held valid throughout the cycle must return inactive for a minimum of t write cycle ...
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... RST , all control, data, and address signals must be powered down when V BATTERY LONGEVITY The DS1744 has a lithium power source that is designed to provide energy for clock activity and clock and RAM data retention when the V sufficient to power the DS1744 continuously for the life of the equipment in which it is installed. For specification purposes, the life expectancy is 10 years at +25° ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground……………………..…….…..……………..-0.3V to +6.0V Operating Temperature Range………………...…………………………..-40°C to +85°C (noncondensing) Storage Temperature Range……………………………………………….-40°C to +85°C (noncondensing) Soldering Temperature………………………….See IPC/JEDEC J-STD-020 Specification (EDIP, Note 7) This is a stress rating only and ...
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DC ELECTRICAL CHARACTERISTICS = 3.3V ±10 Over the operating range PARAMETER Active Supply Current TTL Standby Current ( CMOS Standby Current ( CE ≥ 0.2V) CC Input Leakage ...
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AC CHARACTERISTICS—READ CYCLE (3.3V) = 3.3V ±10 Over the operating range PARAMETER Read Cycle Time Address Access Time Low-Z CE Access Time CE Data Off Time Low-Z OE Access ...
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AC CHARACTERISTICS—WRITE CYCLE (5V) = 5.0V ±10 Over the operating range PARAMETER Write Cycle Time Address Setup Time WE Pulse Width CE Pulse Width Data Setup Time Data Hold Time Data Hold Time Address Hold ...
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WRITE CYCLE TIMING DIAGRAM, WRITE-ENABLE CONTROLLED WRITE CYCLE TIMING DIAGRAM, CHIP-ENABLE CONTROLLED ...
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POWER-UP/DOWN AC CHARACTERISTICS (5V) = 5.0V ±10 Over the operating range PARAMETER Before Power-Down IH V Fall Time PF(MAX) PF(MIN) V Fall Time ...
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POWER-UP/DOWN CHARACTERISTICS (3.3V) = 3.3V ±10 Over the operating range PARAMETER Before Power- IH Down V Fall Time PF(MAX) PF(MIN) V Rise Time ...
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... Battery switchover occurs at the lower of either the battery terminal voltage Data-retention time is at +25°C. 6) Each DS1744 has a built-in switch that disconnects the lithium source until the user first applies V The expected t is defined for DIP modules and assembled PowerCap modules as a cumulative time ...
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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 ...
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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 ...
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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 ...
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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 ...
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... No circuit patent licenses are implied. Maxim/Dallas Semiconductor reserves the right to change the circuitry and specifications without notice at any time The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas Semiconductor Corporation. DS1744/DS1744P Y2K-Compliant, Nonvolatile Timekeeping RAMs © 2006 Maxim Integrated Products • Printed USA ...