M48T37Y-70MH6F STMicroelectronics, M48T37Y-70MH6F Datasheet - Page 11

• Manufacturer Part Number: M48T37Y-70MH6F
• Description: IC TIMEKPR NVRAM 256KB 5V 44-SOH
• Manufacturer: STMicroelectronics
• Series: Timekeeper®r
• Type: Clock/Calendar/NVSRAMr

Specifications of M48T37Y-70MH6F

• Memory Size: 256K (32K x 8)
• Time Format: HH:MM:SS (24 hr)
• Date Format: YY-MM-DD-dd
• Interface: Parallel
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 44-SOH
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-4721-2

M48T37Y, M48T37V
2.3
Note:
Table 4.
1. Valid for ambient operating temperature: T
2. C
3. If E goes low simultaneously with W going low, the outputs remain in the high impedance state.
Data retention mode
With valid V
RAM. Should the supply voltage decay, the RAM will automatically power-fail deselect, write
protecting itself when V
become high impedance, and all inputs are treated as “Don't care.”
A power failure during a WRITE cycle may corrupt data at the currently addressed location,
but does not jeopardize the rest of the RAM's content. At voltages below V
user can be assured the memory will be in a write protected state, provided the V
is not less than t
The M48T37Y/V may respond to transient noise spikes on V
window during the time the device is sampling V
supply lines is recommended. When V
power to the internal battery which preserves data and powers the clock. The internal button
cell will maintain data in the M48T37Y/V for an accumulated period of at least 7 years at
room temperature when V
above V
Normal RAM operation can resume t
For more information on battery storage life refer to the application note AN1012.
t
t
WHQX
WLQZ
Symbol
(except where noted).
t
t
t
t
t
t
t
t
t
t
t
t
t
WLWH
WHAX
DVWH
WHDX
AVWH
EHDX
AVWL
EHAX
DVEH
AVEH
L
AVEL
ELEH
AVAV
= 5 pF.
(2)(3)
(2)(3)
SO
, the battery is disconnected and the power supply is switched to external V
CC
WRITE mode AC characteristics
WRITE cycle time
Address valid to WRITE enable low
Address valid to chip enable low
WRITE enable pulse width
Chip enable low to chip enable high
WRITE enable high to address transition
Chip enable high to address transition
Input valid to WRITE enable high
Input valid to chip enable high
WRITE enable high to input transition
Chip enable high to input transition
WRITE enable low to output Hi-Z
Address valid to WRITE enable high
Address valid to chip enable high
WRITE enable high to output transition
applied, the M48T37Y/V operates as a conventional BYTEWIDE™ static
F
.
CC
CC
Parameter
falls within the V
is less than V
Doc ID 7019 Rev 9
(1)
REC
A
= 0 to 70 °C or –40 to 85 °C; V
CC
after V
drops below V
SO
PFD
. As system power returns and V
(max), V
CC
CC
. Therefore, decoupling of the power
reaches V
Min
70
50
55
30
30
60
60
0
0
0
0
5
5
5
PFD
M48T37Y
SO
–70
, the control circuit switches
(min) window. All outputs
CC
PFD
Max
CC
25
that reach into the deselect
= 4.5 to 5.5 V or 3.0 to 3.6 V
(max).
Min
100
80
80
10
10
50
50
80
80
10
0
0
5
5
M48T37V
Operation modes
–100
PFD
Max
CC
(min), the
50
CC
rises
fall time
Unit
CC
11/30
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
.