DS1554WP-120+ Maxim Integrated Products, DS1554WP-120+ Datasheet
DS1554WP-120+
Specifications of DS1554WP-120+
Related parts for DS1554WP-120+
DS1554WP-120+ Summary of contents
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FEATURES Integrated NV SRAM, Real-Time Clock (RTC), Crystal, Power-Fail Control Circuit, and Lithium Energy Source Clock Registers are Accessed Identically to the Static RAM; These Registers Reside in the 16 Top RAM Locations Century Byte Register ...
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... DS1554P-70IND+ -40°C to +85°C DS1554W-120+ 0°C to +70°C DS1554W-120IND+ -40°C to +85°C DS1554WP-120+ 0°C to +70°C DS1554WP-120IND+ -40°C to +85°C +Denotes a lead(Pb)-free /RoHS-compliant package. *DS9034-PCX+ or DS9034I-PCX+ required (must be ordered separately). **The top mark will include a “+” on lead-free devices. An “IND” anywhere on the top mark indicates an industrial temperature grade device. ...
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DESCRIPTION The DS1554 is a full-function, year 2000-compliant (Y2KC), real-time clock/calendar (RTC) with an RTC alarm, watchdog timer, power-on reset, battery monitor, and 32k x 8 nonvolatile static RAM. User access to all registers within the DS1554 is accomplished with ...
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Figure 1. Block Diagram Table 1. Operating Modes > < V < <V < ...
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DATA-READ MODE The DS1554 is in the read mode whenever CE (chip enable) is low and WE (write enable) is high. The device architecture allows ripple-through access to any valid address location. Valid data will be available after the last ...
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BATTERY LONGEVITY The DS1554 has a lithium power source that is designed to provide energy for the clock activity, and clock and RAM data retention when the V supply is sufficient to power the DS1554 continuously for the life of ...
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Table 2. Register Map ADDRESS 7FFFh 10 Year 7FFEh X X 7FFDh X X 7FFCh X FT 7FFBh X X 7FFAh X 10 Minutes OSC 7FF9h 10 Seconds 7FF8h W R 7FF7h WDS BMB4 BMB3 7FF6h ...
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SETTING THE CLOCK The 8th bit the Control Register is the write bit. Setting the write bit like the read bit, halts updates to the DS1554 (7FF8h-7FFFh) registers. After setting the write bit to a ...
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Table 3. Alarm Mask Bits AM4 AM3 AM2 When the RTC Register values match Alarm Register settings, the Alarm Flag bit (AF) is set to ...
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Figure 4. Backup Mode Alarm Waveforms USING THE WATCHDOG TIMER The watchdog timer can be used to detect an out-of-control processor. The user programs the watchdog timer by setting the desired amount of time-out into the 8-bit Watchdog Register (Address ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground………………………..…………………………………………..-0.3V to +6.0V Storage Temperature Range EDIP ......................………………………………………………………………………………………-40°C to +85°C PowerCap...................…………………..…………………………………………………....................-55°C to +125°C Lead Temperature (soldering, 10s) ......................................................................................................................................+260°C Note: EDIP is wave or hand-soldered only. Soldering Temperature (reflow, PowerCap)…………………………………...……………..............................................+260°C This ...
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DC ELECTRICAL CHARACTERISTICS = 3.3V 10 Over the operating range PARAMETER Active Supply Current TTL Standby Current ( = CMOS Standby Current 0.2V Input Leakage Current ...
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AC CHARACTERISTICS—READ CYCLE (T = Over the operating range) A PARAMETER Read Cycle Time Address Access Time to DQ Low-Z CE Access Time CE Data Off Time Low-Z OE Access Time OE Data Off Time OE Output ...
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Figure 6. Write Cycle Timing, Write-Enable Controlled Figure 7. Write Cycle Timing, Chip-Enable Controlled DS1554 256k, Nonvolatile, Y2K-Compliant Timekeeping RAM ...
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POWER-UP/DOWN CHARACTERISTICS—5V = 5.0V 10 Over the operating range PARAMETER Before Power-Down V Fall Time PF(MAX) PF(MIN) V Fall Time ...
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POWER-UP/DOWN CHARACTERISTICS—3.3V = 3.3V 10 Over the operating range PARAMETER Before Power-Down V Fall Time PF(MAX) PF(MIN) V Rise Time ...
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AC TEST CONDITIONS Output Load 1TTL Gate Input Pulse Levels 3.0V Timing Measurement Reference Levels: Input: 1.5V Output: 1.5V Input Pulse Rise and Fall Times NOTES: 1) Voltage referenced to ground. 2) Typical ...
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... Maxim reserves the right to change the circuitry and specifications without notice at any time 2010 Maxim Integrated Products DS1554 256k, Nonvolatile, Y2K-Compliant Timekeeping RAM DESCRIPTION parameter in the DC Electrical Characteristics tables Maxim and the Dallas logo are registered trademarks of Maxim Integrated Products. PAGES CHANGED 2, 11, 12, 17 ...