English
Language : 

DS1251 Datasheet, PDF (13/22 Pages) Dallas Semiconductor – 4096k NV SRAM with Phantom Clock
POWER-DOWN/POWER-UP TIMING
PARAMETER
SYMBOL
CE at VIH before Power-Down
tPD
VCC Slew from VPF(max) to
tF
VPF(min)( CE at VIH)
VCC Slew from VPF(max) to
tR
VPF(min)( CE at VIH)
CE at VIH after Power-Up
tREC
DS1251/DS1251P
Over the operating range (3.3V)
MIN TYP MAX UNITS NOTES
0
ms
300
ms
0
ms
1.5
2.5
ms
PARAMETER
Expected Data Retention Time
SYMBOL MIN TYP
tDR
10
MAX
(TA = +25°C)
UNITS NOTES
years
9
Warning: Under no circumstances are negative undershoots of any amplitude allowed when device is in
battery-backup mode.
13 of 22