M48Z35AV-10MH6E STMicroelectronics, M48Z35AV-10MH6E Datasheet - Page 9

• Manufacturer Part Number: M48Z35AV-10MH6E
• Description: IC NVSRAM 256KBIT 100NS 28SOIC
• Manufacturer: STMicroelectronics
• Type: NVSRAMr

Specifications of M48Z35AV-10MH6E

• Format - Memory: RAM
• Memory Type: NVSRAM (Non-Volatile SRAM)
• Memory Size: 256K (32K x 8)
• Speed: 100ns
• Interface: Parallel
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC, 28-SOH (8.48mm Width)
• Word Size: 8b
• Organization: 32Kx8
• Density: 256Kb
• Interface Type: Parallel
• Access Time (max): 100ns
• Operating Supply Voltage (typ): 3.3V
• Package Type: SOH
• Operating Temperature Classification: Industrial
• Operating Supply Voltage (max): 3.6V
• Operating Supply Voltage (min): 3V
• Operating Temp Range: -40C to 85C
• Pin Count: 28
• Mounting: Surface Mount
• Supply Current: 50mA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 497-2881-5; M48Z35AV-10MH6

Data Retention Mode
With valid V
as a conventional BYTEWIDE™ static RAM.
Should the supply voltage decay, the RAM will au-
tomatically power-fail deselect, write protecting it-
self when V
(min) window. All outputs become high imped-
ance, and all inputs are treated as “Don't care.”
Note: 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 con-
tent. At voltages below V
assured the memory will be in a write protected
state, provided the V
The M48Z35AY/V may respond to transient noise
spikes on V
during the time the device is sampling V
fore, decoupling of the power supply lines is rec-
ommended.
When V
switches power to the internal battery which pre-
serves data. The internal button cell will maintain
data in the M48Z35AY/V for an accumulated peri-
od of at least 10 years (at 25°C) when V
than V
As system power returns and V
V
supply is switched to external V
tion continues until V
t
t
Also, as V
If the voltage is less than approximately 2.5V, an
internal Battery Not OK (BOK) flag will be set. The
BOK flag can be checked after power up. If the
BOK flag is set, the first WRITE attempted will be
blocked. The flag is automatically cleared after the
first WRITE, and normal RAM operation resumes.
Figure
could be structured.
For more information on Battery Storage Life refer
to the Application Note AN1012.
REC
REC
SO
, the battery is disconnected, and the power
(min). Normal RAM operation can resume
after V
SO
10
CC
.
CC
illustrates how a BOK check routine
CC
CC
CC
CC
drops below V
rises, the battery voltage is checked.
that reach into the deselect window
applied, the M48Z35AY/V operates
exceeds V
falls within the V
CC
CC
fall time is not less than t
PFD
reaches V
PFD
SO
(min), the user can be
(max).
, the control circuit
CC
PFD
CC
. Write protec-
PFD
(max), V
rises above
CC
(min) plus
CC
. There-
is less
PFD
F
.
Figure 10. BOK Check Routine Example
(BATTERY OK)
COMPLEMENT BACK
TO SAME ADDRESS
AT ANY ADDRESS
ADDRESS AGAIN
WRITE ORIGINAL
SAME ADDRESS
DATA BACK TO
COMPLEMENT
WRITE DATA
READ DATA
READ DATA
POWER-UP
CONTINUE
AT SAME
OF FIRST
IS DATA
READ?
YES
M48Z35AY, M48Z35AV
NO
OF LOW BATTERY
(BATTERY LOW)
NOTIFY SYSTEM
(DATA MAY BE
CORRUPTED)
AI00607
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