Datasheet

 2003 Microchip Technology Inc. DS21711C-page 11
24AA01/24LC01B
8.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 8-1.
TABLE 8-1: PIN FUNCTION TABLE
8.1 A0, A1, A2
The A0, A1 and A2 pins are not used by the 24XX01.
They may be left floating or tied to either V
SS or VCC.
8.2 Serial Address/Data Input/Output
(SDA)
The SDA input is a bidirectional pin used to transfer
addresses and data into and out of the device. Since
it is an open-drain terminal, the SDA bus requires a
pull-up resistor to V
CC (typical 10 kΩ for 100 kHz,
2kΩ for 400 kHz).
For normal data transfer, SDA is allowed to change
only during SCL low. Changes during SCL high are
reserved for indicating Start and Stop conditions.
8.3 Serial Clock (SCL)
The SCL input is used to synchronize the data transfer
to and from the device.
8.4 Write-Protect (WP)
This pin must be connected to either VSS or VCC.
If tied to V
SS normal memory operation is enabled
(read/write the entire memory
00-7F).
If tied to V
CC, write operations are inhibited. The entire
memory will be write-protected. Read operations are
not affected.
This feature allows the user to use the 24XX01 as a
serial ROM when WP is enabled (tied to V
CC).
Name PDIP SOIC TSSOP MSOP SOT23 Description
A0 1 1 1 1 — Not Connected
A1 2 2 2 2 — Not Connected
A2 3 3 3 3 — Not Connected
VSS 44 4 42Ground
SDA 5 5 5 5 3 Serial Address/Data I/O
SCL 6 6 6 6 1 Serial Clock
WP 7 7 7 7 5 Write-Protect Input
V
CC 8 8 8 8 4 +1.8V to 5.5V Power Supply