FM24V05 - 512Kb I2C FRAM
5. The master sends Reserved Slave ID 0x86
6. The FM24V05 sends an ACK.
7. The master sends STOP to ensure the device
enters sleep mode.
Sleep Mode
A
low power mode called Sleep Mode is
implemented on both FM24V05 and FM24VN05
devices. The device will enter this low power state
when the Sleep command 86h is clocked-in. Sleep
Mode entry can be entered as follows:
Once in sleep mode, the device draws IZZ current, but
the device continues to monitor the I2C pins. Once
the master sends a Slave Address that the FM24V05
identifies, it will “wakeup” and be ready for normal
operation within tREC (400 µs max.). As an alternative
method of determining when the device is ready, the
master can send read or write commands and look for
an ACK. While the device is waking up, it will
NACK the master until it is ready.
1. The master sends a START command.
2. The master sends Reserved Slave ID 0xF8
3. The master sends the I2C-bus slave address of
the slave device it needs to identify. The last
bit is a ‘Don’t care’ value (R/W bit). Only one
device must acknowledge this byte (the one
that has the I2C-bus slave address).
4. The master sends a Re-START command.
Start
Address
Address
Stop
P
Start
S
By Master
S
Rsvd Slave ID (F8)
A
Slave Address
X
A
Rsvd Slave ID (86)
A
By FM24V05
Acknowledge
Figure 12. Sleep Mode Entry
Rev. 1.1
Feb. 2009
Page 8 of 15
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