© 2008 Microchip Technology Inc. DS22119A-page 11
24AA04H/24LC04BH
8.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 8-1.
TABLE 8-1: PIN FUNCTION TABLE
8.1 Serial Address/Data Input/Output
(SDA)
SDA 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, 2 kΩ 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.
8.2 Serial Clock (SCL)
The SCL input is used to synchronize the data transfer
to and from the device.
8.3 Write-Protect (WP)
The WP pin must be connected to either VSS or VCC.
If tied to V
SS, normal memory operation is enabled
(read/write the entire memory 000h-1FFh).
If tied to V
CC, write operations are inhibited, half of the
memory will be write-protected (100h-1FFh). Read
operations are not affected.
8.4 A0, A1, A2
The A0, A1 and A2 pins are not used by the 24XX04H.
They may be left floating or tied to either V
SS or VCC.
Name PDIP SOIC TSSOP TDFN MSOP SOT-23 Description
A0 1 1 1 1 1 — Not Connected
A1 2 2 2 2 2 — Not Connected
A2 3 3 3 3 3 — Not Connected
V
SS 4 4 4 4 4 2 Ground
SDA 5 5 5 5 5 3 Serial Address/Data I/O
SCL 6 6 6 6 6 1 Serial Clock
WP 7 7 7 7 7 5 Write-Protect Input
V
CC 8 8 8 8 8 4 +1.7V to 5.5V Power Supply
