DocID018338 Rev 2

3/6

TN0440

M24xxx EEPROM: 400 kHz and 1 MHz clock

6

1.2

M24xxx 1 MHz AC tables after 2007

The M24xxx devices running with a 1 MHz clock frequency were introduced by

STMicroelectronics from year 2007. Here again, the M24xxx compatible with the new 1 MHz

I²C-bus specification were designed with timings able to offer the best performances.

•

condition, as explained for the previous 400 kHz table).

•

1.3

Compatibility of 400 kHz and 1 MHz AC timing specifications

It is important to note that:

•

all M24xxx products specified at 1 MHz can run at lower frequencies, and therefore can

run at 400 kHz ;

•

old products designed only for the 400 kHz AC tables (AC tables before 2007) cannot

run at 1 MHz.

Table 3. Access time and Noise filter parameters specified in the 1 MHz AC table

Symbol

Alt

Parameter

M24xxx

Unit

Min. Max. Min. Max.

Data valid time

-

500

-

450

ns

50 (or

more)

-0-

ns

Pulse width ignored (input filter on SCL and

SDA)

50 (or

more)

050

ns