Cypress manual AutoStore or Power Up Recall, Parameter Description CY14B256K Unit Min Max

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								CY14B256K

AutoStore or Power Up RECALL

Parameter			Description			CY14B256K			Unit
Parameter			Description		Min		Max		Unit
					Min		Max
tHRECALL [17]	Power Up RECALL Duration						40		ms
tSTORE [18, 19]	STORE Cycle Duration			Commercial			12.5		ms
				Industrial			15		ms

VSWITCH	Low Voltage Trigger Level						2.65		V
tVCCRISE	VCC Rise Time				150				μs

Figure 12. AutoStore/Power Up RECALL

	STORE occurs only	No STORE occurs
VCC	if a SRAM write	without atleast one
VCC	has happened	SRAM write

VSWITCH
tVCCRISE
AutoStore	tSTORE
tSTORE	tSTORE

POWER-UP RECALL

tHRECALL

tHRECALL

Read & Write Inhibited

Notes

17.tHRECALL starts from the time VCC rises above VSWITCH.

18.If an SRAM Write does not taken place since the last nonvolatile cycle, no STORE takes place.

19.Industrial Grade Devices require 15 ms Max.

Document Number: 001-06431 Rev. *H

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Contents Cypress Semiconductor Corporation 198 Champion Court FeaturesLogic Block Diagram Functional DescriptionPin Definitions Pin ConfigurationsAutoStore Operation Device 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 Watchdog Timer AlarmCalibrating 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 CommandsInputs and Outputs Mode Power RTC CharacteristicsTruth 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 RTCWorldwide Sales and Design Support Products PSoC Solutions Sales, Solutions, and Legal InformationUSB