
R1EX24004AxxS0A
Device Address (A0, A1, A2)
Four devices can be wired for one common data bus line as maximum. Device address pins are used to
distinguish each device and device address pins should be connected to V CC or V SS . When device address
code provided from SDA pin matches corresponding hard-wired device address pins A0 to A2, that one
device can be activated.
Pin Connections for A0 to A2
Pin connection
Max connect
Memory size number
A2
A1
A0
Note
4k bit
4
V CC /V SS *
1
V CC /V SS *
1
× *
2
Use A0 for memory address a8
Note:
1. During floating, “V CC /V SS ” are fixed to V SS .
2. Floating state can be possible.
Write Protect (WP)
When the Write Protect pin (WP) is high, the write protection feature is enabled and operates as shown in
the following table.
Also, acknowledgment "0" is outputted after inputting device address and memory address. After
inputting write data, acknowledgment "1"" (NO ACK) is outputted.
When the WP is low, write operation for all memory arrays are allowed. The read operation is always
activated irrespective of the WP pin status.
Write Protect Area
Write protect area
WP pin status
V IH
V IL
4k bit
Full (4k bit)
Normal read/write operation
REJ03C0353-0101 Rev.1.01 Jan. 9, 2009
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