DS12CR887 Maxim, DS12CR887 Datasheet
DS12CR887
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DS12CR887 Summary of contents
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... RAM with Clear Input ♦ Programmable Square-Wave Output ♦ Automatic Power-Fail Detect and Switch Circuitry ♦ +5.0V or +3.3V Operation ♦ Industrial Temperature Range ♦ DS12CR887 Encapsulated DIP (EDIP) Module with Integrated Battery and Crystal ♦ DS12R887 BGA Module Surface-Mountable Package with Integrated Crystal and Rechargeable Battery ...
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... SO ...................................................................-55°C to +125°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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RTCs with Constant-Voltage Trickle Charger DC ELECTRICAL CHARACTERISTICS (DS12R885 Only 0V 3.2V -40°C to +85°C, unless otherwise noted.) (Note 1) CC BACKUP A PARAMETER SYMBOL V Current (OSC On); BACKUP I BACKUP2 T = ...
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RTCs with Constant-Voltage Trickle Charger AC ELECTRICAL CHARACTERISTICS (V = 2.97V to 3.63V -40°C to +85°C.) (Note PARAMETER SYMBOL Cycle Time Pulse Width, DS Low or R/W High Pulse Width, DS High or R/W Low ...
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RTCs with Constant-Voltage Trickle Charger ASD AD0–AD7 WRITE AD0–AD7 READ AS PW ASH t ASD DS t ASD R ASL AD0–AD7 WRITE _____________________________________________________________________ Motorola Bus Read/Write Timing ASH t ...
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RTCs with Constant-Voltage Trickle Charger 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 OUTPUTS 6 _____________________________________________________________________ t CYC PW ASH t ASED ...
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... SYMBOL Recovery at Power-Up V Fall Time PF(MAX) V PF(MIN) V Rise Time PF(MIN) V PF(MAX) DATA RETENTION (DS12CR887) PARAMETER SYMBOL Expected Data Retention CAPACITANCE (T = +25°C) A PARAMETER SYMBOL Capacitance on All Input Pins Except X1 and X2 Capacitance on IRQ, SQW, and DQ Pins AC TEST CONDITIONS PARAMETER Input Pulse Levels (-5) ...
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RTCs with Constant-Voltage Trickle Charger (V = +3.3V +25°C, unless otherwise noted BACKUP (DS12R885) 625 600 575 550 2.0 2.3 V BACKUP I vs. TEMPERATURE BACKUP (DS12R885) 650 V = 0V, CC 625 V = ...
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... RTCs with Constant-Voltage Trickle Charger X1 X2 DS12R887/ V DS12CR887 CC ONLY V BACKUP CONTROL CHARGER GND DS12R887/ DS12CR887 CS ONLY R INTERFACE MOT RESET AD0–AD7 RLCR PIN NAME SO EDIP BGA MOT 2 — — — — X2 F4, D4, F3, D3, AD0– 4–11 4–11 F2, D2, ...
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RTCs with Constant-Voltage Trickle Charger PIN NAME SO EDIP BGA D5–D8, 12 E1–E8, GND F5– N.C. 20– ...
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... G. Interrupt-request status flag (IRQF) bit is cleared IRQ pin is in the high-impedance state. I. The device is not accessible until RESET is returned high. J. Square-wave output-enable (SQWE) bit is cleared greater than the DS12CR887 and DS12R887, the V CC BACKUP is not applied. The RCLR function is designed to be used through a human CC ...
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... The device is accessed through a multiplexed byte-wide interface, which supports both Intel and Motorola modes. The DS12CR887 EDIP integrates a DS12R885 die with a crystal and battery. The charging circuit on the DS12R885 die is disabled. The battery has sufficient capacity to power the oscillator and registers for five years in the absence +25° ...
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... Refer to Application Note 58: Crystal Considerations with Dallas Real-Time Clocks (RTCs) for more detailed information. The DS12R887 and DS12CR887 are calibrated at the factory to an accuracy of ±1 minute per month at +25°C during data-retention time for the period t ...
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RTCs with Constant-Voltage Trickle Charger methods of avoiding any possible incorrect time and calendar reads are covered later in this text. The three alarm bytes can be used in two ways. First, when the alarm time is written in the ...
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RTCs with Constant-Voltage Trickle Charger 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 0 0 ...
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RTCs with Constant-Voltage Trickle Charger Control Registers The DS12R885 has four control registers that are accessible at all times, even during the update cycle. BIT 7 BIT 6 BIT 5 UIP DV2 Bit 7: Update-In-Progress (UIP). This bit is a ...
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RTCs with Constant-Voltage Trickle Charger 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 ...
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RTCs with Constant-Voltage Trickle Charger 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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... DS12R885. The act of reading Register C clears all active flag bits and the IRQF bit. When the DS12R887 and DS12CR887 are shipped from the factory, the internal oscillator is turned off. This feature prevents the lithium energy cell from being used until it is installed in a system ...
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RTCs with Constant-Voltage Trickle Charger 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 ...
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... Refer to the IPC/JEDEC J-STD-020B standard for Moisture-Sensitive Device (MSD) classifications. The EDIP (DS12CR887) module can be successfully processed through conventional wave-soldering tech- niques so long as temperature exposure to the lithium energy source does not exceed +85°C. Post-solder cleaning with water-washing techniques is acceptable, provided that ultrasonic vibration is not used ...
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... For the latest package outline information and land patterns, AD3 GND AD2 go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package AD1 GND AD0 drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status ...
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... Intel Bus Read Timing diagram; added a note about how the missing 5 2/07 V pin on the DS12CR887 and DS12R887 is internally connected to a lithium BACKUP cell; added the Package Information table. Updated the storage temperature ranges, added the lead temperature, and updated the ...