DS1642-100+ Dallas Semiconductor, DS1642-100+ Datasheet
DS1642-100+
Specifications of DS1642-100+
Related parts for DS1642-100+
DS1642-100+ Summary of contents
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... ORDERING INFORMATION VOLTAGE PART RANGE (V) DS1642-70+ 5.0 DS1642-70 5.0 DS1642-100+ 5.0 DS1642-100 5.0 *DS9034-PCX, DS9034I-PCX, DS9034-PCX+ required (must be ordered separately). A “+" indicates a lead-free product. The top mark will include a “+” symbol on lead-free devices. Nonvolatile Timekeeping RAM PIN CONFIGURATION TOP VIEW ...
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... Power-Supply Input CC DESCRIPTION The DS1642 nonvolatile static RAM and a full-function real-time clock (RTC), both of which are accessible in a bytewide format. The nonvolatile time keeping RAM is pin and function equivalent to any JEDEC-standard SRAM. The device can also be easily substituted in ROM, EPROM, and EEPROM sockets, providing read/write nonvolatility and the addition of the real-time clock function ...
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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 DS1642 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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... The 8th bit of the control register is the write bit. Setting the write bit like the read bit, halts updates to the DS1642 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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... The DS1642 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 DS1642 continuously for the life of the equipment in which it is installed. For specification purposes, the life expectancy is 10 years at 25°C with the internal clock oscillator running in the absence of V power ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground……………………………………………..-0.3V to +7.0V Operating Temperature Range……………………………………………...0°C to +70°C (noncondensing) Storage Temperature Range………………………………………………………………...-20°C to +70°C Soldering Temperature (EDIP, leads)……………………………………..+260°C for 10 seconds (Note 7) This is a stress rating only and ...
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AC CHARACTERISTICS—READ CYCLE PARAMETER Read Cycle Time Address Access Time to DQ Low-Z CE Access Time CE Data Off Time Low-Z OE Access Time OE Data Off Time OE Output Hold from Address READ CYCLE TIMING DIAGRAM ...
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AC CHARACTERISTICS—WRITE CYCLE (V = 5.0V ±10 0°C to 70°C PARAMETER Write Cycle Time Address Setup Time Pulse Width WE Pulse Width CE Data Setup Time Data Hold Time Address Hold Time Data Off Time WE ...
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WRITE CYCLE TIMING DIAGRAM—WRITE-ENABLE CONTROLLED WRITE CYCLE TIMING DIAGRAM—CHIP-ENABLE CONTROLLED ...
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POWER-UP/POWER-DOWN AC CHARACTERISTICS (T = 0°C to +70°C) A PARAMETER Before Power-Down Fall Time: V (MAX Fall Time: V (MIN Rise Time: V ...
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... Voltages are referenced to ground. 2) Typical values are at 25°C and nominal supplies. 3) Outputs are open. 4) Data retention time is at 25°C. 5) Each DS1642 has a built-in switch that disconnects the lithium source until V user. The expected t is defined as a cumulative time in the absence power is first applied by the user ...
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... For the latest package outline information www.maxim-ic.com/DallasPackInfo.) DS1642 24-PIN PACKAGE Maxim/Dallas Semiconductor cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim/Dallas Semiconductor product. ...