DS12R887 Maxim Integrated Products, DS12R887 Datasheet
DS12R887
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DS12R887 Summary of contents
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... The DS12R885 is accessed through a multiplexed byte-wide interface, which supports both Intel and Motorola modes. The DS12CR887 and DS12R887 integrate the DS12R885 die with a crystal and battery. Embedded Systems Utility Meters ...
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RTC with Constant-Voltage Trickle Charger ABSOLUTE MAXIMUM RATINGS Voltage Range on V Pin Relative to Ground .....-0.3V to +6.0V CC Operating Temperature Range ...........................-40°C to +85°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the ...
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RTC 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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RTC 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 PW Pulse Width, DS High or R/W ...
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RTC 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 ASED ...
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RTC 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 VALID OUTPUTS 6 _____________________________________________________________________ t CYC PW ASH t ...
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RTC with Constant-Voltage Trickle Charger POWER-UP/POWER-DOWN CHARACTERISTICS (T = -40°C to +85°C) (Note 1) A PARAMETER SYMBOL Recovery at Power-Up V Fall Time PF(MAX) V PF(MIN) V Rise Time PF(MIN) V PF(MAX) CAPACITANCE (T ...
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RTC with Constant-Voltage Trickle Charger (V = +3.3V +25°C, unless otherwise noted vs. V BACKUP (DS12R885) 625 600 575 550 2.0 2.3 V BACKUP I vs. TEMPERATURE BACKUP (DS12R885) 650 V = 0V, CC 625 ...
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... RTC with Constant-Voltage Trickle Charger X1 X2 DS12R887/ V DS12CR887 CC ONLY V BACKUP GND DS12R887/ DS12CR887 ONLY CS 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, AD7 F1, D1 ...
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RTC with Constant-Voltage Trickle Charger PIN NAME SO EDIP BGA D5–D8 E1–E8, GND F5– R 16, 16 N.C. 20– ...
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RTC with Constant-Voltage Trickle Charger PIN NAME SO EDIP BGA RESET IRQ — — V BACKUP RCLR 21 — SQW A6–A8 B1–B8 C6–C8 Reset Input. ...
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... V at +25°C. CC The DS12R887 BGA includes a crystal and a recharge- able battery. A fully charged battery can power the oscil- lator and registers (typical current at +25°C) in the absence of V for approximately 11 days (10% of ...
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... Refer to Application Note 58: Crystal Considerations with Dallas Real-Time Clocks 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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RTC with Constant-Voltage Trickle Charger 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 ...
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RTC 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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RTC 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 DV1 Bit 7: Update-In-Progress (UIP). This bit is ...
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RTC with Constant-Voltage Trickle Charger BIT 7 BIT 6 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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RTC 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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RTC 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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RTC with Constant-Voltage Trickle Charger Handling, PC Board Layout, and Assembly The EDIP and BGA packages contain a quartz tuning- fork crystal. Pick-and-place equipment can be used, but precautions should be taken to ensure that exces- sive shocks are avoided. ...
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... RTC with Constant-Voltage Trickle Charger Pin Configurations (continued) TOP VIEW (BUMP SIDE DOWN DS12R887 RESET IRQ V SQW CC 4 RCLR V MOT BGA Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied ...