DS1500WE+ Maxim Integrated Products, DS1500WE+ Datasheet
DS1500WE+
Specifications of DS1500WE+
Related parts for DS1500WE+
DS1500WE+ Summary of contents
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... Office Equipment Consumer Electronics Pin Configuration and Typical Operating Circuit appear at end of data sheet. ORDERING INFORMATION PART TEMP RANGE DS1500WE 0C to +70C DS1500WE+ 0C to +70C DS1500WEN -40°C to +85°C DS1500WEN+ -40°C to +85°C DS1500YE 0C to +70C DS1500YE+ 0C to +70C DS1500YEN -40° ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground……………………………………………………………..-0.5V to +6.0V ………………………………………………………… Operating Temperature Range …………………………………………………………………. Storage Temperature Range ………………………………………………. Soldering Temperature Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These ...
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DC ELECTRICAL CHARACTERISTICS ( -40°C to +85°C PARAMETER Battery Current, BB32 = 0, EOSC = 0 Battery Current, BB32 = 0, EOSC = 1 V Current BB32 = 1, SQW Open BAUX CRYSTAL SPECIFICATIONS* ...
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AC OPERATING CHARACTERISTICS (continued) = 3.3V 10 -40°C to +85°C.) A CCI PARAMETER Read Cycle Time Address Access Time Low-Z CS Access Time CS 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-Select-Controlled A0- DQ0-DQ7 VALID DATA OUTPUT DATA ...
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Figure 4. Burst Mode Timing Waveform A 0 – – POWER-UP/DOWN CHARACTERISTICS PARAMETER CS, CEI Before Power-Fail IH ...
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Figure 5. 5V Power-Up/Down Waveform Timing V CCI V PF(MAX) V PF(MIN RST INPUTS RECOGNIZED OUTPUTS VALID 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 6) A PARAMETER Kickstart-Input Pulse Width Wakeup/Kickstart Power-On Timeout Note: Time intervals shown above are referenced in Wakeup/Kickstart. Figure 6. Wakeup/Kickstart Timing Diagram Note 1: Limits at -40°C are not production tested and are ...
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PIN DESCRIPTION PIN NAME Square-Wave Output. When enabled, the SQW pin outputs a 32.768kHz square wave. If the square 1 SQW wave (E32K) and battery-backup 32kHz (BB32) bits are enabled, power is provided absent. CC Kickstart ...
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Figure 7. Block Diagram X1 32.768kHz CLOC K OSCILLATOR X2 V BAT V BAT POWER CONTROL V BAUX WRITE PROTECTIO , N GND KS CEI Figure 8. Typical Crystal Layout LOCAL GROUND PLANE (LAYER 2) CRYSTAL CLOCK ALARM AND WATCHDOG ...
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DETAILED DESCRIPTION The RTC registers are double buffered into an internal and external set. The user has direct access to the external set. Clock/calendar updates to the external set of registers can be disabled and enabled to allow the user ...
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DATA RETENTION MODE The DS1500 is fully accessible and data can be written and read only when V when V falls below the power-fail point V CCI and SRAM are blocked from any access. While in the data retention mode, ...
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SETTING THE CLOCK It is recommended to halt updates to the external set of double buffered RTC registers when writing to the clock. The (TE) bit should be used as described above before loading the RTC registers with the desired ...
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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 DS1500 is in the ...
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Control A Register (0Eh) Bit 7 Bit 6 BLF1 BLF2 BLF1, Valid RAM and Time Bit 1 (0Eh Bit 7); BLF2, Valid RAM and Time Bit 2 (0Eh Bit 6) These status bits give the condition of any batteries attached ...
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Control B Register (0Fh) Bit 7 Bit TE, Transfer Enable Bit (0Fh Bit 7) When the TE bit is 1, the update transfer functions normally by advancing the counts once per second. When the TE bit is ...
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The watchdog timer operates in two modes, repetitive and single-shot. If WDE is 1 and the ...
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Intervals CCI the timing diagram. During Interval 2, PWR remains active, and IRQ is driven to its active-low level, ...
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... No circuit patent licenses are implied. Maxim/Dallas Semiconductor reserves the right to change the circuitry and specifications without notice at any time The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas Semiconductor Corporation. DS1500 Y2K Watchdog RTC with Nonvolatile Control ...