Cypress CY14B256K Manual de usuario Pagina 1

CY14B256K256 Kbit (32K x 8) nvSRAM with Real Time ClockCypress Semiconductor Corporation • 198 Champion Court • San Jose, CA 95134-1709 • 408-943-2600

CY14B256KDocument Number: 001-06431 Rev. *H Page 10 of 28Figure 5. Interrupt Block DiagramFigure 6. RTC Recommended Component ConfigurationWDF - Wa

CY14B256KDocument Number: 001-06431 Rev. *H Page 11 of 28Table 3. RTC Register Map[5, 6]RegisterBCD Format Data [5]Function/RangeD7 D6 D5 D4 D3 D2 D

CY14B256KDocument Number: 001-06431 Rev. *H Page 12 of 28Table 4. Register Map Detail0x7FFFTime Keeping - YearsD7 D6 D5 D4 D3 D2 D1 D010s Years Year

CY14B256KDocument Number: 001-06431 Rev. *H Page 13 of 280X7FF8Calibration/ControlD7 D6 D5 D4 D3 D2 D1 D0OSCEN 0 CalibrationSignCalibrationOSCEN Osci

CY14B256KDocument Number: 001-06431 Rev. *H Page 14 of 280x7FF4Alarm - HoursD7 D6 D5 D4 D3 D2 D1 D0M 10s Alarm Hours Alarm HoursContains the alarm va

CY14B256KDocument Number: 001-06431 Rev. *H Page 15 of 28Maximum RatingsExceeding maximum ratings may impair the useful life of thedevice. These user

CY14B256KDocument Number: 001-06431 Rev. *H Page 16 of 28Data Retention and EnduranceParameter Description Min UnitDATARData Retention 20 YearsNVCNon

CY14B256KDocument Number: 001-06431 Rev. *H Page 17 of 28AC Switching Characteristics ParameterDescription25 ns 35 ns 45 nsUnitMin Max Min Max Min Ma

CY14B256KDocument Number: 001-06431 Rev. *H Page 18 of 28AC Switching Characteristics (continued)ParameterDescription25 ns 35 ns 45 nsUnitMin Max Min

CY14B256KDocument Number: 001-06431 Rev. *H Page 19 of 28AutoStore or Power Up RECALLParameter DescriptionCY14B256KUnitMin MaxtHRECALL [17]Power Up R

CY14B256KDocument Number: 001-06431 Rev. *H Page 2 of 28Pin ConfigurationsFigure 1. 48-Pin SSOP Pin DefinitionsPin Name Alt IO Type DescriptionA0–A1

CY14B256KDocument Number: 001-06431 Rev. *H Page 20 of 28Software Controlled STORE/RECALL Cycles [20, 21]ParameterAlt. ParameterDescription25 ns 35

CY14B256KDocument Number: 001-06431 Rev. *H Page 21 of 28Hardware STORE CycleParameterAlt. ParameterDescriptionCY14B256KUnitMin MaxtDELAY [22]Time Al

CY14B256KDocument Number: 001-06431 Rev. *H Page 22 of 28RTC CharacteristicsParameter Description Test Conditions Min Max UnitIBAK [25]RTC Backup Cur

CY14B256KDocument Number: 001-06431 Rev. *H Page 23 of 28Part Numbering NomenclatureCY 14 B 256 K - SP 25 X C T Option:T-Tape and ReelBlank - Std.Spe

CY14B256KDocument Number: 001-06431 Rev. *H Page 24 of 28Ordering InformationAll the below mentioned parts are Pb-free. Contact your local Cypress sa

CY14B256KDocument Number: 001-06431 Rev. *H Page 25 of 28Package DiagramsFigure 17. 48-Pin Shrunk Small Outline Package (51-85061)51-85061-*C[+] Fee

CY14B256KDocument Number: 001-06431 Rev. *H Page 26 of 28Document History PageDocument Title: CY14B256K 256 Kbit (32K x 8) nvSRAM with Real Time Cloc

CY14B256KDocument Number: 001-06431 Rev. *H Page 27 of 28*H 2663934 GVCH/PYRS 02/24/09 Updated Features sectionUpdated pin definition of WE pinUpdate

Document Number: 001-06431 Rev. *H Revised February 24, 2009 Page 28 of 28All products and company names mentioned in this document are the trademark

CY14B256KDocument Number: 001-06431 Rev. *H Page 3 of 28Device OperationThe CY14B256K nvSRAM consists of two functionalcomponents paired in the same

CY14B256KDocument Number: 001-06431 Rev. *H Page 4 of 28tDELAY, multiple SRAM READ operations take place. If a WRITEis in progress when HSB is pulled

CY14B256KDocument Number: 001-06431 Rev. *H Page 5 of 28Low Average Active PowerCMOS technology provides the CY14B256K the benefit ofdrawing signific

CY14B256KDocument Number: 001-06431 Rev. *H Page 6 of 28Table 1. Mode SelectionCE WE OEA13–A0 Mode IO PowerH X X X Not Selected Output High Z Standb

CY14B256KDocument Number: 001-06431 Rev. *H Page 7 of 28Real Time Clock OperationnvTIME OperationThe CY14B256K consists of internal registers that co

CY14B256KDocument Number: 001-06431 Rev. *H Page 8 of 28Calibrating the ClockThe RTC is driven by a quartz controlled oscillator with a nominalfreque

CY14B256KDocument Number: 001-06431 Rev. *H Page 9 of 28Power MonitorThe CY14B256K provides a power management scheme withpower fail interrupt capabi