DS1557P-100 DALLAS [Dallas Semiconductor], DS1557P-100 Datasheet
DS1557P-100
Related parts for DS1557P-100
DS1557P-100 Summary of contents
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... Battery voltage level indicator flag Power-fail write protection allows for 10% V power supply tolerance CC Lithium energy source is electrically disconnected to retain freshness until power is applied for the first time ORDERING INFORMATION DS1557P-XXX (5-Volt) - access -100 100 ns access *DS1557WP-XXX (3.3 Volt) -120 120 ns access ...
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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 to access static ...
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DS1557 OPERATING MODES Table > < V < < DATA READ ...
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BATTERY LONGEVITY The DS1557 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 DS1557 continuously for the life of ...
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DS1557 REGISTER MAP Table 2 ADDRESS 7FFFh 10 Year 7FFEh X X 7FFDh X X 7FFCh X FT 7FFBh X X 7FFAh X 10 MINUTES 7FF9h 10 SECONDS OSC 7FF8h W R 7FF7h WDS BMB4 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 DS1557 (7FF8h-7FFFh) registers. After setting the write bit to a ...
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ALARM MASK BITS Table 3 AM4 AM3 AM2 When the RTC Register values match Alarm Register settings, the Alarm Flag bit (AF) is set to ...
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BACK-UP MODE ALARM WAVEFORMS Figure 4 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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POWER-ON DEFAULT STATES Upon application of power to the device, the following register bits are set WDS=0, BMB0-BMB4=0, RB0-RB1=0, AE=0, ABE=0. ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature ...
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DC ELECTRICAL CHARACTERISTICS PARAMETER Active Supply Current TTL Standby Current ( = V CE CMOS Standby Current = 0.2V Input Leakage Current (any input) Output Leakage Current (any output) Output Logic 1 Voltage (I = -1.0 ...
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READ CYCLE, AC CHARACTERISTICS 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 Hold from Address READ CYCLE, AC ...
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WRITE CYCLE, AC CHARACTERISTICS PARAMETER Write Cycle Time Address Access Time Pulse Width WE Pulse Width CE Data Setup Time Data Hold time Data Hold time Address Hold Time Address Hold Time Data Off Time WE Write Recovery Time WRITE ...
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WRITE CYCLE TIMING, WRITE ENABLE CONTROLLED Figure 6 WRITE CYCLE TIMING, CHIP ENABLE CONTROLLED Figure DS1557 ...
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POWER-UP/DOWN CHARACTERISTICS PARAMETER Before Power-Down V Fall Time PF(MAX) V PF(Min) V Fall Time PF(MIN Rise Time PF(MIN) V PF(MAX) V ...
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POWER-UP/DOWN CHARACTERISTICS PARAMETER Before Power-Down V Fall Time PF(MAX) V PF(Min) V Rise Time PF(MIN) V PF(MAX High RST PF Expected Data Retention Time (Oscillator ...
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AC TEST CONDITIONS Output Load: 100 pF + 1TTL Gate Input Pulse Levels: 0.0 to 3.0 Volts Timing Measurement Reference Levels: Input: 1.5V Output: 1.5V Input Pulse Rise and Fall Times NOTES: 1. Voltage referenced to ground. 1. ...
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... DS1557P NOTE: Dallas Semiconductor recommends that PowerCap Module bases experience one pass through solder reflow oriented with the label side up (“live-bug”). Hand Soldering and touch-up: Do not touch or apply the soldering iron to leads for more than 3 seconds. To solder, apply flux to the pad, heat the lead frame pad and apply solder. To remove the part, apply flux, heat the lead frame pad until the solder reflows and use a solder wick to remove solder ...
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... DS1557P WITH DS9034PCX ATTACHED PKG DIM MIN 0.920 A B 0.955 C 0.240 0.052 D E 0.048 F 0.015 0.020 DS1557 INCHES NOM MAX 0.925 0.930 0.960 0.965 0.245 0.250 0.055 0.058 0.050 0.052 0.020 0.025 0.025 0.030 ...
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RECOMMENDED POWERCAP MODULE LAND PATTERN PKG DIM MIN DS1557 INCHES NOM MAX - 1.050 - - 0.826 - - 0.050 - - 0.030 - - 0.112 - ...