DS1500_11 MAXIM [Maxim Integrated Products], DS1500_11 Datasheet

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DS1500_11

Manufacturer Part Number
DS1500_11
Description
Y2K Watchdog RTC with Nonvolatile Control
Manufacturer
MAXIM [Maxim Integrated Products]
Datasheet
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.
GENERAL DESCRIPTION
The DS1500 is a full-function, year 2000-compliant
real-time clock/calendar (RTC) with an alarm,
watchdog timer, power-on reset, battery monitors,
256 bytes of on-board nonvolatile (NV) SRAM, NV
control for backing up an external SRAM, and a
32.768kHz output. User access to all registers within
the DS1500 is accomplished with a byte-wide
interface, as shown in Figure 7. The RTC registers
contain century, year, month, date, day, hours,
minutes, and seconds data in 24-hour binary-coded
decimal (BCD) format. Corrections for day of month
and leap year are made automatically.
APPLICATIONS
Remote Systems
Battery-Backed Systems
Telecom Switches
Office Equipment
Consumer Electronics
Pin Configuration and Typical Operating Circuit appear at
end of data sheet.
ORDERING INFORMATION
+Denotes a lead(Pb)-free/RoHS-compliant device.
*
A “+” anywhere on the top mark indicates a lead(Pb)-free/RoHS-compliant device. An “N” indicates an industrial temperature range device.
DS1500WE+
DS1500WEN+
DS1500YE+
DS1500YEN+
PART
-40°C to +85°C
-40°C to +85°C
TEMP RANGE
0°C to +70°C
0°C to +70°C
Y2K Watchdog RTC with Nonvolatile Control
VOLTAGE (V)
1 of 20
3.3
3.3
5.0
5.0
FEATURES
BCD-Coded Century, Year, Month, Date, Day,
Hours, Minutes, and Seconds with Automatic
Leap-Year Compensation Valid Up to the Year
2100
Programmable Watchdog Timer and RTC
Alarm
Century Register; Y2K-Compliant RTC
Automatic Battery Backup and Write
Protection to External SRAM
+5V or +3.3V Operation
Precision Power-On Reset
Power-Control Circuitry Supports System
Power-On from Date/Day/Time Alarm or Key
Closure
256 Bytes User NV RAM
Auxiliary Battery Input
Accuracy Better than ±1 Minute/Month at
+25°C
Day-of-Week/Date Alarm Register
Battery Voltage-Level Indicator Flags
Optional Industrial Temperature Range: -40°C
to +85°C
PIN-PACKAGE
32 TSOP
32 TSOP
32 TSOP
32 TSOP
T OP MARK*
0 B
DS1500W
DS1500WN
DS1500Y
DS1500YN
DS1500

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DS1500_11 Summary of contents

Page 1

Y2K Watchdog RTC with Nonvolatile Control GENERAL DESCRIPTION The DS1500 is a full-function, year 2000-compliant real-time clock/calendar (RTC) with an alarm, watchdog timer, power-on reset, battery monitors, 256 bytes of on-board nonvolatile (NV) SRAM, NV control for backing up an ...

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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground……………………………………………………………..-0.5V to +6.0V Operating Temperature Range (Industrial) Operating Temperature Range (Commercial) …………………………………………………………………. Storage Temperature Range Lead Temperature (soldering, 10s)………. ………………………………….…………………………………… Soldering Temperature (reflow) Stresses beyond those listed under “Absolute Maximum ...

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PARAMETER Output Voltage (I = 50μA) CCO2 Battery Leakage Current DC ELECTRICAL CHARACTERISTICS ( Over the Operating Range PARAMETER Battery Current, BB32 = 0, EOSC = 0 Battery Current, BB32 = 0, EOSC = ...

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AC OPERATING CHARACTERISTICS (continued 3.3V ±10 Over the Operating Range.) CCI A PARAMETER Read Cycle Time Address Access Time Low-Z CS Access Time CS Data Off Time Low-Z (0°C to ...

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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 t WC VALID WEW t WEZ DATA OUTPUT DATA INPUT t WC VALID t t ...

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Figure 4. Burst Mode Timing Waveform A0–A4 OE, WE DQ0–DQ7 POWER-UP/DOWN CHARACTERISTICS PARAMETER CS, CEI Before Power-Fail IH V Fall Time CCI PF(MAX) PF(MIN) V Fall Time CCI ...

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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 CLOCK OSCILLATOR X2 V BAT V BAT POWER CONTROL V BAUX WRITE PROTECTION, GND KS CEI Figure 8. Typical Crystal Layout LOCAL GROUND PLANE (LAYER 2) CRYSTAL CLOCK ALARM AND WATCHDOG COUNTDOWN AND POWER-ON ...

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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 ...

Page 16

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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applied within the timeout period, then the system power-on sequence continues, as shown in Intervals 2 CCI the timing diagram. During Interval 2, PWR remains active, and IRQ is driven to its active-low level, ...

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PIN CONFIGURATION TOP VIEW Maxim DS1500 TSOP (8mm x 20mm) TYPICAL OPERATING CIRCUIT V CC RST IRQ CPU DQ0–DQ7 PACKAGE INFORMATION For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or ...

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REVISION HISTORY REVISION DATE Updated the Features, Ordering Information, Absolute Maximum 11/11 Ratings, and Package Information; corrected the operating temperature range for the EC tables Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in ...

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