CY14C256I_13 Datasheet, PDF (2/41 Pages) Cypress Semiconductor – 256-Kbit (32 K x 8) Serial (I2C) nvSRAM with Real Time Clock

CY14C256I
CY14B256I
CY14E256I
Contents
Pinouts .............................................................................. 3
Pin Definitions .................................................................. 3
I2C Interface ...................................................................... 4
Protocol Overview ............................................................ 4
I2C Protocol – Data Transfer ....................................... 4
Data Validity ................................................................ 5
START Condition (S) ................................................... 5
STOP Condition (P) ..................................................... 5
Repeated START (Sr) ................................................. 5
Byte Format ................................................................. 5
Acknowledge / No-acknowledge ................................. 5
High-Speed Mode (Hs-mode) ..................................... 6
Slave Device Address ................................................. 7
Memory Control Register ............................................ 8
Command Register ..................................................... 8
Write Protection (WP) .................................................. 9
AutoStore Operation .................................................... 9
Hardware STORE and HSB pin Operation ................. 9
Hardware RECALL (Power Up) ................................... 9
Write Operation ......................................................... 10
Read Operation ......................................................... 10
Memory Slave Access ............................................... 10
RTC Registers Slave Access .................................... 14
Control Registers Slave ............................................. 16
Serial Number ................................................................. 18
Serial Number Write .................................................. 18
Serial Number Lock ................................................... 18
Serial Number Read .................................................. 18
Device ID ......................................................................... 19
Executing Commands Using Command Register ..... 19
Real Time Clock Operation ............................................ 20
nvTIME Operation ..................................................... 20
Clock Operations ....................................................... 20
Reading the Clock ..................................................... 20
Setting the Clock ....................................................... 20
Backup Power ........................................................... 20
Stopping and Starting the Oscillator .......................... 20
Calibrating the Clock ................................................. 21
Alarm ......................................................................... 21
Watchdog Timer ........................................................ 21
Programmable Square Wave Generator ................... 22
Power Monitor ........................................................... 22
Backup Power Monitor .............................................. 22
Interrupts ................................................................... 22
Interrupt Register ....................................................... 22
Flags Register ........................................................... 23
Maximum Ratings ........................................................... 29
Operating Range ............................................................. 29
DC Electrical Characteristics ........................................ 29
Data Retention and Endurance ..................................... 30
Thermal Resistance ........................................................ 30
AC Test Loads and Waveforms ..................................... 31
AC Test Conditions ........................................................ 31
RTC Characteristics ....................................................... 31
AC Switching Characteristics ....................................... 32
Switching Waveforms .................................................... 32
nvSRAM Specifications ................................................. 33
Switching Waveforms .................................................... 33
Software Controlled STORE/RECALL Cycles .............. 34
Switching Waveforms .................................................... 34
Hardware STORE Cycle ................................................. 35
Switching Waveforms .................................................... 35
Ordering Information ...................................................... 36
Ordering Code Definitions ......................................... 36
Package Diagram ............................................................ 37
Acronyms ........................................................................ 38
Document Conventions ................................................. 38
Units of Measure ....................................................... 38
Document History Page ................................................. 39
Sales, Solutions, and Legal Information ...................... 41
Worldwide Sales and Design Support ....................... 41
Products .................................................................... 41
PSoC Solutions ......................................................... 41
Document Number: 001-65230 Rev. *G
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