DS1501 Maxim, DS1501 Datasheet
DS1501
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DS1501 Summary of contents
Page 1
... Minute/Month at +25°C Day-of-Week/Date Alarm Register Crystal Select Bit Allow RTC to Operate with 6pF or 12.6pF Crystal (DS1501) Battery Voltage-Level Indicator Flags Available as Chip (DS1501) or Stand-Alone Encapsulated DIP Module with Embedded Battery and Crystal (DS1511) Underwriters Laboratories (UL) Recognized TEMP RANGE PIN-PACKAGE 28 DIP (0.600) 0° ...
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... Battery Switchover Voltage (Notes 3, 6) Battery Leakage Current DS1501/DS1511 Y2KC Watchdog Real-Time Clocks ……………………………………………….. …………………...………………………………….... ...
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... WE Pulse Width CE Pulse Width Data Setup Time Data Hold Time Address Hold Time WE Data-Off Time Write Recovery Time Pulse Width, OE, WE High Pulse Width, OE, WE Low DS1501/DS1511 Y2KC Watchdog Real-Time Clocks = 0V -40°C to +85°C.) A SYMBOL CONDITIONS I (Note 7) BAT1 ...
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... Data Hold Time Address Hold Time WE Data-Off Time Write Recovery Time Pulse Width, OE, WE High Pulse Width, OE, WE Low Figure 1. Read Cycle Timing A0– DQ0-DQ7 DS1501/DS1511 Y2KC Watchdog Real-Time Clocks = 3.3V ±10 -40°C to +85°C SYMBOL CONDITIONS ...
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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 DS1501/DS1511 Y2KC Watchdog Real-Time Clocks t WC VALID WEW WEZ DH DATA OUTPUT DATA INPUT VALID DATA INPUT ...
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... On) CAPACITANCE (T = +25°C) A PARAMETER Capacitance on All Input Pins Capacitance on IRQ, PWR, RST, and DQ Pins AC TEST CONDITIONS OUTPUT LOAD (Y) 50pF + 1TTL Gate (W) 25pF + 1 TTL Gate DS1501/DS1511 Y2KC Watchdog Real-Time Clocks SYMBOL CONDITIONS ...
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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. DS1501/DS1511 Y2KC Watchdog Real-Time Clocks ...
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... DS1511. DR Note 10: If the oscillator is not enabled, the startup time of the oscillator after V Note 11: Typical values are at +25°C, nominal (active) supply, unless otherwise noted. DS1501/DS1511 Y2KC Watchdog Real-Time Clocks SYMBOL CONDITIONS t ...
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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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... V BAT POWER CONTROL V BAUX WRITE PROTECTION, AND POWER-ON GND RESET KS Figure 9. Typical Crystal Layout LOCAL GROUND PLANE (LAYER 2) CRYSTAL DS1501/DS1511 Y2KC Watchdog Real-Time Clocks CLOCK ALARM AND WATCHDOG COUNTDOWN DS1501/DS1511 X1 X2 GND IRQ SQW CLOCK AND CONTROL REGISTERS A0–A4 DQ0– ...
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... DATA WRITE MODE The DS1501/DS1511 are in write mode whenever CE and WE are in their active state. The start of a write is referenced to the latter occurring transition WE. The addresses must be held valid throughout the cycle. ...
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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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... DS1511W+ 3.3 DS1511Y+ 5.0 +Denotes a lead(Pb)-free/RoHS-compliant package “+” anywhere on the top mark denotes a lead(Pb)-free package IND denotes an industrial temperature device. DS1501/DS1511 Y2KC Watchdog Real-Time Clocks TEMP RANGE PIN-PACKAGE 28 DIP (0.600) -40C to +85 (0.300) 0C to +70 (0.300) -40 ...
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... IRQ 5 24 DS1501 DQ0 11 18 DQ1 12 17 DQ2 13 16 GND 14 15 DIP, SO DS1501/DS1511 Y2KC Watchdog Real-Time Clocks SQW 2 BAUX BAT V 4 BAT BAUX SQW PWR 8 GND X1 ...
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... DQ0–DQ7 PACKAGE INFORMATION For the latest package outline information and land patterns www.maxim-ic.com/packages. PACKAGE TYPE 28-pin DIP (600 mils) 28-pin SO (300 mils) 28-pin TSOP (8mm x 13.4mm) 28-pin EDIP (720 mils) DS1501/DS1511 Y2KC Watchdog Real-Time Clocks V CC CRYSTAL ...
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... © 2009 Maxim Integrated Products DS1501/DS1511 Y2KC Watchdog Real-Time Clocks DESCRIPTION ...