BQ4852Y Datasheet, PDF (2/16 Pages) Texas Instruments – RTC Module With 512Kx8 NVSRAM

bq4852Y
Functional Description
Figure 1 is a block diagram of the bq4852Y. The follow-
ing sections describe the bq4852Y functional operation,
including memory and clock interface, data-retention
modes, power-on reset timing, watchdog timer activa-
tion, and interrupt generation.
Internal
Quartz
Crystal
Time-
Base
-.. 8
Oscillator
3
4
CE
OE
DQ -DQ
07
AD₀ -AD₁₈
WE
V _CC
Internal
Battery
Control/Status
Registers
P
Clock/Calendar,
Alarm,
Bus
and Control Bytes
I/F
User Buffer
(16 Bytes)
Power-
Fail
Control
Write-
Protect
Storage
Registers
(524,288 Bytes)
-.. 64
-.. 64
16 : 1 MUX
Reset and
Interrupt
Generator
Clock/Calendar
Update
RST
INT
BD-962
Truth Table
VCC
CE
< VCC (max.)
VIH
VIL
> VCC (min.)
VIL
VIL
< VPFD (min.) > VSO
X
≤ VSO
X
Figure 1. Block Diagram
OE
WE
Mode
DQ
Power
X
X
Deselect
High Z
Standby
X
VIL
Write
DIN
Active
VIL
VIH
Read
DOUT
Active
VIH
VIH
Read
High Z
Active
X
X
Deselect
High Z
CMOS standby
X
X
Deselect
High Z
Battery-backup mode
Aug. 1996
2