DS1501-DS1511 DALLAS [Dallas Semiconductor], DS1501-DS1511 Datasheet
DS1501-DS1511
Related parts for DS1501-DS1511
DS1501-DS1511 Summary of contents
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... GENERAL DESCRIPTION The DS1501/DS1511 are full-function, year 2000- compliant real-time clock/calendars (RTCs) with an RTC alarm, watchdog timer, power-on reset, battery monitors, 256 bytes NV SRAM, and a 32.768kHz output. User access to all registers within the DS1501/DS1511 is accomplished with a byte-wide interface, as shown in Figure 8. The RTC registers ...
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... Operating Temperature Range, DS1511……………………………………………………………….……..0°C to +70°C Storage Temperature Range, DS1501 Storage Temperature Range, DS1511………………………………………………………………….…..-40°C to +70°C Soldering Temperature (DIP, Module)… ...
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DC ELECTRICAL CHARACTERISTICS ( 0°C to +70° PARAMETER Battery Current, BB32 = 0, EOSC = 0 Battery Current, BB32 = 0, EOSC = 1 V Current BB32 = 1, SQW Open BAUX CRYSTAL ...
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AC OPERATING CHARACTERISTICS (V = 3.3V ±10 0°C to +70° PARAMETER Read Cycle Time Address Access Time Low-Z CE Access Time CE Data Off Time Low-Z (0°C to +85°C) ...
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Figure 2. Write Cycle Timing, Write-Enable Controlled A0– DQ0–DQ7 Figure 3. Write Cycle Timing, Chip-Enable Controlled A0- DQ0-DQ7 t WC VALID WEW WEZ DATA OUTPUT DATA INPUT ...
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Figure 4. Burst Mode Timing Waveform A 0 – – POWER-UP/DOWN CHARACTERISTICS PARAMETER Before Power-Fail IH V ...
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Figure 5. 3.3V Power-Up/Down Waveform Timing Figure 6. 5V Power-Up/Down Waveform Timing Warning: Under no circumstances are negative undershoots, of any amplitude, allowed when device is in battery- backup mode ...
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WAKEUP/KICKSTART TIMING (T = +25°C) (Figure 7) A PARAMETER Kickstart-Input Pulse Width Wakeup/Kickstart Power-On Timeout Note: Time intervals shown above are referenced in Wakeup/Kickstart. Figure 7. Wakeup/Kickstart Timing Diagram ...
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... The crystal is attached directly to the X1 and X2 pins. There is no need for external capacitors or resistors. An external 32.768kHz oscillator can also drive the DS1501. In this configuration, the X1 pin is connected to the external oscillator signal and the X2 pin is floated. For more information about ...
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... BAT POWER CONTROL V BAUX WRITE PROTECTION, AND POWER-ON GND RESET KS Figure 9. Typical Crystal Layout LOCAL GROUND PLANE (LAYER 2) CRYSTAL CLOCK ALARM AND WATCHDOG COUNTDOWN Dallas Semiconductor DS1501/DS1511 X1 X2 GND IRQ SQW CLOCK AND CONTROL REGISTERS A0–A4 DQ0–DQ7 ...
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... This feature provides a high degree of data security during unpredictable system operation caused by low V The DS1501/DS1511 have interrupt ( IRQ ), power control ( PWR ), and reset ( RST ) outputs that can be used to control CPU activity. The IRQ interrupt or RST outputs can be invoked as the result of a time-of-day alarm, CPU watchdog alarm kickstart signal ...
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... If the square-wave and battery-backup 32kHz functions are enabled, V always provides power for the square-wave output, when the device is in battery-backup mode. AUXILIARY BATTERY The V input is provided to supply power from an auxiliary battery for the DS1501/DS1511 kickstart and square- BAUX wave output features in the absence of V when V is not applied to the device ...
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... External circuit noise coupled into the oscillator circuit can result in the clock running fast. A standard 32.768kHz quartz crystal should be directly connected to the DS1501 X1 and X2 oscillator pins. The crystal selected for use should have a specified load capacitance (C accordingly. An external 32.768kHz oscillator can also drive the DS1501. When using an external oscillator the X2 pin must be left open. The DS1511 contains an embedded crystal and is factory trimmed to be better than ± ...
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... The alarm can be programmed to activate on a specific day of the month, day of the week, or repeat every day, hour, minute, or second. It can also be programmed to go off while the DS1501/DS1511 are in the battery-backed state of operation to serve as a system wakeup. Alarm mask bits AM1 to AM4 control the alarm mode. Table 3 shows the possible settings ...
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... IRQF bit. This bit is cleared by reading the register or writing WDF, Watchdog Flag (0Eh Bit 1) If the processor does not access the DS1501/DS1511 with a write within the period specified in addresses 0CH and 0DH, the WDF bit is set to 1. WDF is cleared by writing ...
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... TE bit is written to 0, any update transfer is inhibited and the program can initialize the time and calendar bytes without an update occurring in the midst of initializing. Read cycles can be executed in a similar manner read/write bit that is not modified by internal functions of the DS1501/DS1511. CS, Crystal Select Bit (0Fh Bit 6) When CS is set to 0, the oscillator is configured for operation with a crystal that has a 6pF specified load capacitance ...
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... WDE = 1 and WDS = 1: WDF is set, the RST pin pulses low, and WDE resets to 0. WAKEUP/KICKSTART The DS1501/DS1511 incorporate a wakeup feature, which powers predetermined day/date and time by activating the PWR output pin. Additionally, the kickstart feature allows the system to be powered up in response to a low-going transition on the KS pin, without operating voltage applied to the V can be applied upon such events as key closure or a modem-ring-detect signal ...
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... TDF and/or KSF by reading the flags register or by writing TDF and KSF long as no other interrupt within the DS1501/DS1511 is pending, the IRQ line is taken inactive once these bits are reset, and execution of the application software can proceed. During this time, the wakeup and kickstart functions can be used to generate status and interrupts ...
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... Semiconductor DS1511 DQ0 11 18 DQ1 12 17 DQ2 13 16 GND 14 15 720-MIL MODULE TOP MARK DS1501YN DS1501YEN DS1501YSN DS1501WN DS1501WEN DS1501WSN DS1511Y DS1511W BAUX OE 1 N.C. SQW BAT SQW V 5 BAUX N.C. ...
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... CRYSTAL PWR SQW RST IRQ V BAUX Dallas V Semiconductor BAT DS1501 CE GND GND PWR SQW RST IRQ V BAUX Dallas Semiconductor DS1511 CE ...