DS1556W-120IND+ Maxim Integrated Products, DS1556W-120IND+ Datasheet
DS1556W-120IND+
Specifications of DS1556W-120IND+
Related parts for DS1556W-120IND+
DS1556W-120IND+ 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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... 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. *DS9034-PCX+ or DS9034I-PCX+ required (must be ordered separately). **A “+” in top mark denotes a lead(Pb)-free device. An “IND” anywhere on the top mark indicates an industrial temperature grade device. ...
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DESCRIPTION The DS1556 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 128k x 8 nonvolatile static RAM. User access to all registers within the DS1556 is accomplished with a ...
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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 ...