Icc figure for M24SR02-Y

[ASpen]

I am experiencing spurious lockups of the I²C interface of an M24SR02-Y (see a separate post). Due to time/development constraints, it may be the easiest to simply cycle power to the device when this problem is detected. The datasheet is, however, not completely clear (to me) on supply current requirements.

Is the Icc in Table72 ("RF supply current) stated as 100mA only present in the AC0-AC1 circuit?

The name "Icc" seems to imply that it is through the Vcc pin of the chip, which would mean that we could not supply the device from a microcontroller I/O pin.

Or is the Vcc supply current only the I²C supply current Icc1 as indicated on Table 76 i.e. max of between 200µA and 250µA? If that is the case, then direct supply from a microcontroller I/O pin would be fine.

[Peter BENSCH · Accepted solution]

Table 73 contains the absolute max ratings. Please don't be confused by Icc, as it means the energy coming from the NFC/RFID coil. For the RF supply current AC0 - AC1 it is max 100mA - where the device survives. Footnote 3 gives also some hint: Based on characterization, not tested in production. Maximum adsorbed power = 100 mW @ 7.5 A/m

When your question is answered, please close this topic by choosing Select as Best.

/Peter

[ASpen]

Thank you Peter!

[JP Miller]

​Dear Customer,

In order to work properly, M24SR chips require when an RF operation is going on, power from the RF field  and the minimum current is specified by the Icc value of the table 73 (rev 12 of the datasheet) 'Absolute maximum ratings' of the datasheet.

It also requires power on Vcc  for proper I2C operation, specified in the table 77 'I2C DC characteristics ' as  Icc0 to Icc3 values. The current to be supplied depends on the type of operation that is being performed on the I2C bus (opening an I2C session,  doing a read or a write) and whether RF is on or not. The values quoted as 200µA and 250µA apply for the Readbinary operation.

Have a good day.

Regards,