DS1553 Maxim, DS1553 Datasheet
DS1553
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DS1553 Summary of contents
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... RTC alarm, watchdog timer, power-on reset, battery monitor, and nonvolatile static RAM. User access to all registers within the DS1553 is accomplished with a byte-wide interface as shown in Figure 1. The RTC registers contain century, year, month, date, day, hours, minutes, and seconds data in 24-hour BCD format. ...
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PIN DESCRIPTION PIN NAME EDIP PowerCap RST A12 A10 23 ...
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... DETAILED DESCRIPTION The RTC registers in the DS1553 are double-buffered into an internal and external set. The user has direct access to the external set. Clock/calendar updates to the external set of registers can be disabled and enabled to allow the user to access static data. Assuming the internal oscillator is turned on, the internal set of registers is continuously updated ...
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... If the address inputs are changed while AA output data hold time (t ) but will then go indeterminate until the next address access. OH DATA WRITE MODE The DS1553 is in write mode whenever referenced to the latter occurring transition of the cycle. and must return inactive for a minimum read or write cycle ...
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... All control, data, and address signals must be powered down when V BATTERY LONGEVITY The DS1553 has a lithium power source that is designed to provide energy for the clock activity and clock and RAM data retention when the V supply is sufficient to power the DS1553 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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... The MSB of the Seconds register (B7 of 1FF9h). Setting stops the oscillator; setting starts the oscillator. The DS1553 is shipped from Dallas Semiconductor with the clock oscillator turned off, with the bit set to 1 ...
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... RTC registers and allows normal operation to resume. CLOCK ACCURACY (DIP MODULE) The DS1553 is guaranteed to keep time accuracy to within 1 minute per month at +25C. The RTC is calibrated at the factory by Dallas Semiconductor using nonvolatile tuning elements and does not require additional calibration ...
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... The alarm can be programmed to activate on a specific day of the month or repeat every day, hour, minute, or second. It can also be programmed to go off while the DS1553 is in the battery-backed state of operation to serve as a system wakeup. Alarm mask bits AM1–AM4 control the alarm mode. Table 3 shows the possible settings ...
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Figure 2. Clearing IRQ Waveforms , CE Figure 3. Clearing IRQ Waveforms CE = Ø The /FT pin can also be activated in the battery-backed mode. The IRQ occurs and both ABE and AE are set. The ABE and AE ...
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USING THE WATCHDOG TIMER The watchdog timer can be used to detect an out-of-control processor. The user programs the watchdog timer by setting the desired amount of timeout into the 8-bit Watchdog register (Address 1FF7h). The five Watchdog register bits ...
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... Soldering Temperature (reflow)……………………………………..................................................+260°C 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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DC ELECTRICAL CHARACTERISTICS (V = 3.3V ±10 Over the operating range PARAMETER Active Supply Current TTL Standby Current ( CMOS Standby Current (CE 0.2V) CC Input Leakage Current (Any Input) ...
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READ CYCLE, AC CHARACTERISTICS (V = 5.0V ± Over the operating range PARAMETER Read Cycle Time Address Access Time Low-Z CE Access Time CE Data Off Time Low-Z ...
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WRITE CYCLE, AC CHARACTERISTICS (V = 5.0V ±10 Over the operating range PARAMETER Write Cycle Time Address Access Time WE Pulse Width CE Pulse Width Data Setup Time Data Hold time Address Hold Time WE Data ...
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Figure 6. Write Cycle Timing, Write-Enable Controlled Figure 7. Write Cycle Timing, Chip-Enable Controlled ...
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POWER-UP/DOWN CHARACTERISTICS (V = 5.0V ± 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 (V = 3.3V ± Over the operating range PARAMETER Before Power-Down IH V Fall Time PF(MAX) PF(MIN) V Rise Time ...
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... IRQ RST 6) Data retention time is at +25C. 7) Each DS1553 has a built-in switch that disconnects the lithium source until V user. The expected t is defined for DIP modules as a cumulative time in the absence from the time power is first applied by the user. ...
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... DQ7 20 DQ6 CE DQ5 19 DQ7 DQ4 18 DQ6 DQ3 17 DQ5 DQ2 16 DQ4 DQ1 DQ0 15 DQ3 GND www.maxim-ic.com/packages PACKAGE CODE OUTLINE NO. MDP28+2 PC1 DS1553 GND ...
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... © 2010 Maxim Integrated Products DS1553 64kB, Nonvolatile, Year-2000-Compliant Timekeeping RAM DESCRIPTION ...