DS1251 Datasheet, PDF (11/22 Pages) Dallas Semiconductor – 4096k NV SRAM with Phantom Clock

DS1251/DS1251P
PHANTOM CLOCK AC ELECTRICAL CHARACTERISTICS
Over the operating range (5V)
PARAMETER
SYMBOL MIN TYP MAX UNITS NOTES
Read Cycle Time
t_RC
65
ns
CE Access Time
t_CO
55
ns
OE Access Time
t_OE
55
ns
CE to Output Low-Z
t_COE
5
ns
OE to Output Low-Z
t_OEE
5
ns
CE to Output High-Z
t_OD
25
ns
5
OE to Output High-Z
t_ODO
25
ns
5
Read Recovery
Write Cycle Time
Write Pulse Width
Write Recovery
Data Setup Time
Data Hold Time
t_RR
10
t_WC
65
t_WP
55
t_WR
10
t_DS
30
t_DH
0
ns
ns
ns
3
ns
10
ns
4
ns
4
CE Pulse Width
t_CW
60
ns
RESET Pulse Width
t_RST
65
ns
POWER-DOWN/POWER-UP TIMING
PARAMETER
SYMBOL
CE at V_IH before Power-Down
t_PD
V_CC Slew from V_PF(max) to
t_F
V_PF(min)( CE at V_PF)
V_CC Slew from V_PF(min) to V_SO
t_FB
Over the operating range (3.3V)
MIN TYP MAX UNITS NOTES
0
ms
300
ms
10
ms
V_CC Slew from V_PF(max) to
V_PF(min)( CE at V_PF)
CE at V_IH after Power-Up
t_R
0
t_REC
1.5
ms
2.5
ms
PARAMETER
Expected Data Retention Time
SYMBOL MIN TYP
t_DR
10
MAX
(T_A = +25°C)
UNITS NOTES
years
9
Warning: Under no circumstances are negative undershoots of any amplitude allowed when device is in
battery-backup mode.
11 of 22