DS1556P Maxim Integrated Products, Inc., DS1556P Datasheet
DS1556P
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DS1556P 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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... EMOD (0.740a) 5.0 32 EMOD (0.740a) 5.0 32 EMOD (0.740a) 5.0 32 EMOD (0.740a) 5.0 34 PowerCap* 5.0 34 PowerCap* 5.0 34 PowerCap* 5.0 34 PowerCap* 3.3 32 EMOD (0.740a) 3.3 32 EMOD (0.740a) 3.3 32 EMOD (0.740a) 3.3 34 PowerCap* 3.3 34 PowerCap* 3.3 34 PowerCap* 3.3 34 PowerCap TOP MARK** DS1556-070 DS1556070 DS1556-070 DS1556070 DS1556P-70 DS1556P+70 DS1556P-70 DS1556P+70 DS1556W-120 DS1556W-120 DS1556W120 DS1556WP-120 DS1556WP+120 DS1556WP-120 DS1556WP+120 ...
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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 < ...
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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………………………………………………………………...-40°C to +85°C Soldering Temperature…………………………………...See IPC/JEDEC Standard J-STD-020A (Note 8) This is a stress rating only and functional operation of the device at these or ...
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DC ELECTRICAL CHARACTERISTICS (V = 3.3V ±10%, Over the Operating Range.) CC PARAMETER Active Supply Current TTL Standby Current ( CMOS Standby Current (CE ³ 0.2V) CC Input Leakage Current (Any Input) Output Leakage ...
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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— 5.0V ±10%, Over the Operating Range.) CC 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. 3.3V ±10%, Over the Operating Range.) CC PARAMETER Before IH Power-Down V Fall Time PF(MAX) PF(MIN) V Rise Time PF(MIN) PF(MAX) V ...
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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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PACKAGE INFORMATION (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/DallasPackInfo.) DS1556 1M, Nonvolatile, Y2K-Compliant Timekeeping RAM PKG 32-PIN DIM MIN A IN. 1.670 MM 38.42 ...
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... PACKAGE INFORMATION (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/DallasPackInfo.) DS1556 1M, Nonvolatile, Y2K-Compliant Timekeeping RAM DS1556P PKG DIM MIN A 0.920 B 0.980 C — D 0.052 E 0.048 F 0.015 G 0.025 ...
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... PACKAGE INFORMATION (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/DallasPackInfo.) DS1556P WITH DS9034PCX ATTACHED DS1556 1M, Nonvolatile, Y2K-Compliant Timekeeping RAM ...
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... The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas Semiconductor Corporation. ...