DS1556P-70IND Maxim Integrated Products, DS1556P-70IND Datasheet
DS1556P-70IND
Specifications of DS1556P-70IND
Related parts for DS1556P-70IND
DS1556P-70IND Summary of contents
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Rev 9/10 www.maxim-ic.com 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 ...
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... BAT ORDERING INFORMATION PART TEMP RANGE DS1556-70+ 0°C to +70°C DS1556-70IND+ -40°C to +85°C DS1556P-70+ 0°C to +70°C DS1556P-70IND+ -40°C to +85°C DS1556W-120+ 0°C to +70°C DS1556W-120IND+ -40°C to +85°C DS1556WP-120+ 0°C to +70°C DS1556WP-120IND+ -40°C to +85°C +Denotes a lead(Pb)-free/RoHS-compliant package. ...
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... This design allows the PowerCap to be mounted on top of the DS1556P after the completion of the surface mount process. Mounting the PowerCap after the surface mount process prevents damage to the crystal and battery due to the high temperatures required for solder reflow ...
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Figure 1. Block Diagram Table 1. Operating Modes > < V < <V ...
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OE signal will be high during a write cycle. However, OE can be active provided that care is taken with the data bus to avoid bus contention low prior to WE transitioning low, ...
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CLOCK OPERATIONS Table 2 and the following paragraphs describe the operation of RTC, alarm, and watchdog functions. Table 2. Register Map ADDRESS 1FFFFh 10 Year 1FFFEh X X 1FFFDh X X 1FFFCh X Ft 1FFFBh X ...
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READING THE CLOCK When reading the RTC data recommended to halt updates to the external set of double-buffered RTC Registers. This puts the external registers into a static state allowing data to be read without register values changing ...
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USING THE CLOCK ALARM The alarm settings and control for the DS1556 reside within Registers 1FFF2h to 1FFF5h. Register 1FFF6h contains two alarm enable bits: Alarm Enable (AE) and Alarm in Backup Enable (ABE). The AE and ABE bits must ...
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Figure 3. Clearing IRQ Waveforms CE=0 The IRQ/FT pin can also be activated in the battery-backed mode. The IRQ/FT will go low if an alarm occurs and both ABE and AE are set. The ABE and AE bits are cleared ...
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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 1FFF7h). The five Watchdog Register bits ...
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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 hand or wave-soldered only. Soldering Temperature (reflow, PowerCap)………………………………….....................................................................+260°C This is a ...
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DC ELECTRICAL CHARACTERISTICS = 3.3V 10%, Over the Operating Range PARAMETER Active Supply Current TTL Standby Current ( CMOS Standby Current (CE V - 0.2V) CC Input Leakage Current (Any Input) Output Leakage Current ...
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AC CHARACTERISTICS—READ CYCLE (Over the Operating Range) PARAMETER Read Cycle Time Address Access Time Low-Z CE Access Time CE Data Off Time Low-Z OE Access Time OE Data Off Time Output Hold from Address ...
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Figure 6. Write Cycle Timing, Write-Enable Controlled Figure 7. Write Cycle Timing, Chip-Enable Controlled DS1556 1M, Nonvolatile, Y2K-Compliant Timekeeping RAM ...
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POWER-UP/DOWN CHARACTERISTICS—5V = 5.0V 10%, Over the Operating Range PARAMETER Before IH Power-Down V Fall Time PF(MAX) PF(MIN) V Fall Time PF(MIN ...
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POWER-UP/DOWN CHARACTERISTICS—3.3V = 3.3V 10%, Over the Operating Range PARAMETER Before IH Power-Down V Fall Time PF(MAX) PF(MIN) V Rise Time PF(MIN) PF(MAX) to ...
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AC TEST CONDITIONS Output Load 1TTL Gate Input Pulse Levels: 0.0 to 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 DS1556 1M, Nonvolatile, Y2K-Compliant Timekeeping RAM DESCRIPTION Maxim and the Dallas logo are registered trademarks of Maxim Integrated Products. PAGES CHANGED parameter in the DC 2, 11, 12, 17 ...