DS12885S Maxim Integrated Products, DS12885S Datasheet
DS12885S
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DS12885S Summary of contents
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... Optional 28-Pin PLCC Surface Mount Package 32-Pin TQFP (DS12885) RESET ♦ Optional Encapsulated DIP (EDIP) Package with RCLR Integrated Crystal and Battery (DS12887, DS12887A, DS12C887, DS12C887A) ♦ Optional Industrial Temperature Range Available SQW ♦ Underwriters Laboratory (UL) Recognized V BAT ______________________________________________ Maxim Integrated Products Real-Time Clocks Features 1 ...
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Real-Time Clocks ABSOLUTE MAXIMUM RATINGS Voltage Range on V Pin Relative to Ground .....-0.3V to +6.0V CC Operating Temperature Range ................................................... Commercial (noncondensing) .............................0°C to +70°C Operating Temperature Range ................................................... Industrial (noncondensing)...............................-40°C to +85°C Storage Temperature Range EDIP ..................................................................-40°C to ...
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DC ELECTRICAL CHARACTERISTICS ( 3.0V over the operating range, unless otherwise noted.) (Note 2) CC BAT A PARAMETER SYMBOL V Current (OSC On); BAT T = +25° 3.0V A BACKUP V Current ...
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Real-Time Clocks AS t ASD AD0–AD7 WRITE AD0–AD7 READ AS t ASD DS t ASD R ASL AD0–AD7 WRITE 4 _____________________________________________________________________ Motorola Bus Read/Write Timing PW ASH t ASED t CYC ...
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AS t ASD DS t ASD R/W CS AD0–AD7 IRQ Release Delay Timing DS RESET IRQ t IRDS PF(MAX) V PF(MIN) RECOGNIZED INPUTS VALID OUTPUTS t CYC PW ASH t ASED ...
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Real-Time Clocks POWER-UP/POWER-DOWN CHARACTERISTICS (T = -40°C to +85°C) (Note 2) A PARAMETER SYMBOL Recovery at Power-Up V Fall Time PF(MAX) V PF(MIN) V Rise Time PF(MIN) V PF(MAX) DATA RETENTION (T = +25°C) ...
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T = +25°C, unless otherwise noted vs. V BAT1 BAT vs. TEMPERATURE +85°C CC 300 250 0°C +70°C +40°C 200 -40°C 150 2.5 2.8 3.0 3.5 3.3 V (V) BAT X1 ...
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Real-Time Clocks PIN SO, EDIP PLCC TQFP PDIP — — 5–10, 4–11 4– 15, 20 12, 17 ...
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PIN SO, NAME EDIP PLCC TQFP PDIP 11, 15, 20, 22 16, 20, 13, 18, 23, 25 RESET Connection. This ...
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Real-Time Clocks PIN SO, EDIP PLCC TQFP PDIP — (DS12887A DS12C887A ____________________________________________________________________ Pin Description (continued) NAME Active-Low Interrupt Request Output. ...
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Detailed Description The DS12885 family of RTCs provide 14 bytes of real- time clock/calendar, alarm, and control/status registers and 114 bytes (113 bytes for DS12C887 and DS12C887A) of nonvolatile, battery-backed static RAM. A time-of-day alarm, three maskable interrupts with a ...
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Real-Time Clocks Clock Accuracy The accuracy of the clock is dependent upon the accu- racy of the crystal and the accuracy of the match between the capacitive load of the oscillator circuit and the capacitive load for which the crystal ...
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The three alarm bytes can be used in two ways. First, when the alarm time is written in the appropriate hours, minutes, and seconds alarm locations, the alarm inter- rupt is initiated at the specified time each day, if the ...
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Real-Time Clocks Table 2B. Time, Calendar, and Alarm Data Modes—Binary Mode ( ADDRESS BIT 7 BIT 6 BIT 5 00H 0 0 01H 0 0 02H 0 0 03H 0 0 AM/PM 04H AM/PM 0 ...
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Control Registers The real-time clocks have four control registers that are accessible at all times, even during the update cycle. MSB BIT 7 BIT 6 BIT 5 UIP DV2 Bit 7: Update-In-Progress (UIP). This bit is a status flag that ...
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Real-Time Clocks MSB BIT 7 BIT 6 BIT 5 SET PIE Bit 7: SET. When the SET bit is 0, the update transfer functions normally by advancing the counts once per second. When the SET bit is written to 1, ...
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MSB BIT 7 BIT 6 BIT 5 IRQF PF Bit 7: Interrupt Request Flag (IRQF). This bit is set to 1 when any of the following are true PIE = AIE = ...
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Real-Time Clocks Century Register (DS12C887/DS12C887A Only) The century register at location 32h is a BCD register designed to automatically load the BCD value 20 as the year register changes from 99 to 00. The MSB of this register is not ...
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Table 3. Periodic Interrupt Rate and Square-Wave Output Frequency SELECT BITS t PERIODIC PI REGISTER A INTERRUPT RATE RS3 RS2 RS1 RS0 None 3.90625ms 7.8125ms ...
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... Real-Time Clocks TOP VIEW MOT AD0 4 AD1 5 DS12885 AD2 6 DS12885S AD3 7 AD4 8 AD5 9 AD6 10 AD7 11 GND 12 SO, PDIP NOTE: THE DS12887A AND DS12C887A CANNOT BE STORED OR SHIPPED IN CONDUCTIVE MATERIAL THAT WILL GIVE A CONTINUITY PATH BETWEEN THE RAM CLEAR PIN AND GROUND. 20 ____________________________________________________________________ ...
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... EDIP 28 PLCC TQFP PROCESS: CMOS SUBSTRATE CONNECTED TO GROUND ____________________________________________________________________ Real-Time Clocks Ordering Information TOP MARK* DS12885 DS12885 DS12885Q DS12885Q DS12885Q DS12885Q DS12885S DS12885S DS12885S DS12885 DS12885 DS12887 DS12887A DS12C887 DS12C887AA Thermal Information THETA-JA (°C/W) THETA-JC (°C/ 105 Package Information PACKAGE CODE DOCUMENT NO ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 22 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc ...