Datasheet

DocID023994 Rev 3 7/34
M24C04-W M24C04-R M24C04-F Signal description
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2 Signal description
2.1 Serial Clock (SCL)
The signal applied on the SCL input is used to strobe the data available on SDA(in) and to
output the data on SDA(out).
2.2 Serial Data (SDA)
SDA is an input/output used to transfer data in or data out of the device. SDA(out) is an
open drain output that may be wire-OR’ed with other open drain or open collector signals on
the bus. A pull-up resistor must be connected from Serial Data (SDA) to V
CC
(Figure 10
indicates how to calculate the value of the pull-up resistor).
2.3 Chip Enable (E1, E2)
These input signals are used to set the value that is to be looked for on the two bits (b3, b2)
of the 7-bit device select code. These inputs must be tied to V
CC
or V
SS
to establish the
device select code as shown in
Table 2. When not connected (left floating), these inputs are
read as low (0,0).
2.4 Write Control (WC)
This input signal is useful for protecting the entire contents of the memory from inadvertent
write operations. Write operations are disabled to the entire memory array when Write
Control (
WC) is driven high. Write operations are enabled when Write Control (WC) is either
driven low or left floating.
When Write Control (WC) is driven high, device select and address bytes are
acknowledged, Data bytes are not acknowledged.
2.5 V
SS
(ground)
V
SS
is the reference for the V
CC
supply voltage.