Cypress CY14B256K manual 2663934, Updated Features section, Pin, Operation, Added footnote

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CY14B256K

Document Title: CY14B256K 256 Kbit (32K x 8) nvSRAM with Real Time Clock

Document Number: 001-06431

	Rev.	ECN	Orig. of Change	Submission	Description of Change
	Rev.	ECN	Orig. of Change	Date	Description of Change
				Date

	*H	2663934	GVCH/PYRS	02/24/09	Updated Features section
					Updated pin definition of	WE	pin
					Updated “Reading the clock”, “Backup Power”, “Stopping and
					starting the Oscillator” and “Alarm” descriptions under RTC
					operation
					Modified “Figure 4. RTC Recommended Component Configuration”
					Added footnote 4
					Added footnote 6
					Added default values to RTC Register Map” table
					Updated flag register description in Register Map Detail” table
					Added Industrial specs for 25ns and 35ns speed
					Changed VIH from vcc+0.3 to Vcc+0.5
					Added “Data Retention and Endurance” table on page 15
					Added thermal resistance values
					Added alternate parameters in the AC switching characteristics
					table
					Renamed tOH to tOHA
					Changed tHRECALL from 20 to 40ms
					Changed tRECALL spec from 100μs to 170μs (Including tss of 70us)
					Renamed tAS to tSA
					Renamed tGHAX to tHA
					Renamed tHLHX to tPHSB
					Updated Figure 16
					Added truth table for SRAM operations

Document Number: 001-06431 Rev. *H

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Contents Cypress Semiconductor Corporation 198 Champion Court FeaturesLogic Block Diagram Functional DescriptionPin Definitions Pin ConfigurationsDevice Operation AutoStore OperationHardware Store HSB Operation Data Protection Hardware Recall Power UpSoftware Store Software RecallCurrent versus Cycle Time Low Average Active Power Best PracticesMode Selection A13-A0 Power Real Time Clock Operation Alarm Watchdog TimerCalibrating the Clock Flags Register Power MonitorInterrupts Interrupt RegisterInterrupt Block Diagram WDF Oscf RTC Register Map5 BCD Format Data Function/RangeTime Keeping Minutes 0x7FFA Register Map Detail Time Keeping Years 0x7FFF 10s YearsTime Keeping Months 0x7FFE 10s Month Date Time Keeping Hours 0x7FFBInterrupt Status/Control 0x7FF6 Alarm Day 0x7FF5Register Map Detail Calibration/Control 0X7FF8 0x7FF7When the Flags register is read or on power-up Register Map Detail Alarm Hours 0x7FF4 10s Alarm HoursTo ignore the hours value Alarm Minutes 0x7FF3 Alarm Seconds 0x7FF2Range DC Electrical CharacteristicsMaximum Ratings Operating RangeAC Test Conditions Data Retention and EnduranceCapacitance Thermal ResistanceParameter Sram Read Cycle AC Switching CharacteristicsDescription 25 ns 35 ns 45 ns Min Max Unit Sram Write Cycle Parameter Cypress AltParameter Description CY14B256K Unit Min Max AutoStore or Power Up RecallParameter Alt Description 25 ns 35 ns 45 ns Unit Min Max Software Controlled STORE/RECALL Cycles 20Hardware Store Cycle Soft Sequence CommandsRTC Characteristics Inputs and Outputs Mode PowerTruth Table For Sram Operations Part Numbering Nomenclature CY 14 B 256 K SP 25 X C T Ordering Information Pin Shrunk Small Outline Package Package DiagramsOrig. of Change Submission Description of Change Date Document HistoryAdded default values to RTC Register Map table Updated Features sectionUpdated Reading the clock, Backup Power, Stopping Starting the Oscillator and Alarm descriptions under RTCSales, Solutions, and Legal Information Worldwide Sales and Design Support Products PSoC SolutionsUSB