M48T201V-70MH1 STMICROELECTRONICS [STMicroelectronics], M48T201V-70MH1 Datasheet - Page 4

• Manufacturer Part Number: M48T201V-70MH1
• Description: 3.3V-5V TIMEKEEPER CONTROLLER
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

M48T201Y, M48T201V
DESCRIPTION
The M48T201Y/V are self-contained devices that
include a real time clock (RTC), programmable
alarms, a watchdog timer, and a square wave out-
put which provides control of up to 512K x 8 of ex-
ternal low-power static RAM. Access to all RTC
functions and the external RAM is the same as
conventional bytewide SRAM. The 16 TIME-
KEEPER
hour, minute, second, calibration, alarm, century,
watchdog, and square wave output data. External-
ly attached static RAMs are controlled by the
M48T201Y/V via the G
The 44-pin, 330mil SOIC provides sockets with
gold plated contacts at both ends for direct con-
nection to a separate SNAPHAT
taining the battery and crystal. The unique design
allows the SNAPHAT battery package to be
Figure 2. Logic Diagram
4/33
RSTIN1
RSTIN2
A0-A18
WDI
®
W
G
E
registers offer year, month, date, day,
19
M48T201Y
M48T201V
V CC
V SS
CON
and E
CON
®
8
housing con-
IRQ/FT
RST
G CON
E CON
SQW
V OUT
signals.
DQ0-DQ7
AI02240
mounted on top of the SOIC package after the
completion of the surface mount process.
Insertion of the SNAPHAT housing after reflow
prevents potential battery damage due to the high
temperatures required for device surface-mount-
ing. The SNAPHAT housing is keyed to prevent
reverse insertion. The SOIC and battery packages
are shipped separately in plastic anti-static tubes
or in Tape & Reel form. For the 44-lead SOIC, the
battery/crystal package (e.g., SNAPHAT) part
number
19., page
Caution: Do not place the SNAPHAT battery/crys-
tal top in conductive foam as this will drain the lith-
ium button-cell battery.
Table 1. Signal Names
DQ0-DQ7
RSTIN1
RSTIN2
A0-A18
IRQ/FT
G
E
SQW
V
RST
WDI
V
V
NC
CON
OUT
W
CON
G
E
CC
SS
31).
is
“M4Txx-BR12SH”
Address Inputs
Data Inputs / Outputs
Reset 1 Input
Reset 2 Input
Reset Output (Open Drain)
Watchdog Input
Chip Enable Input
Output Enable Input
WRITE Enable Input
RAM Chip Enable Output
RAM Enable Output
Interrupt / Frequency Test Output
(Open Drain)
Square Wave Output
Supply Voltage Output
Supply Voltage
Ground
Not Connected Internally
(see
Table