M48T35AV_07 datasheet(12/28 Pages) STMICROELECTRONICS

Il numero della parte	M48T35AV

Spiegazioni elettronici	3.3V, 256Kbit (32Kbit x 8) TIMEKEEPER짰 SRAM

PDF	28 Pages

Scroll/Zoom	100%

Produttore elettronici	STMICROELECTRONICS [STMicroelectronics]

Homepage	http://www.st.com

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12 / 28 page

Operation modes

M48T35AV

12/28

Also, as VCC rises, the battery voltage is checked. 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 8

illustrates how a BOK check routine could be structured.

For more information on Battery Storage Life refer to the Application Note AN1012.

Figure 8.

Checking the BOK flag status

READ DATA

AT ANY ADDRESS

AI00607

IS DATA

COMPLEMENT

OF FIRST

READ?

(BATTERY OK)

POWER-UP

YES

WRITE DATA

COMPLEMENT BACK

TO SAME ADDRESS

READ DATA

AT SAME

ADDRESS AGAIN

NOTIFY SYSTEM

OF LOW BATTERY

(DATA MAY BE

CORRUPTED)

WRITE ORIGINAL

DATA BACK TO

SAME ADDRESS

(BATTERY LOW)

CONTINUE

M48T35AV Scheda tecnica(PDF) 12 Page - STMicroelectronics