24AA025 Datasheet, PDF (15/42 Pages) Microchip Technology – I2C™ Serial EEPROM Family Data Sheet

24AAXX/24LCXX/24FCXX
5.7.1
CONTIGUOUS ADDRESSING
ACROSS MULTIPLE DEVICES
Chip Select bits A2, A1 and A0 can be used to expand
the contiguous address space by adding up to eight
24XXs on the same bus. Software can use the three
address bits of the control byte as the three Most
Significant bits of the address byte. For example, in the
24XX32 devices, software can use A0 of the control
byte as address bit A12; A1 as address bit A13; and A2
as address bit A14 (Table 5-1). It is not possible to
sequentially read across device boundaries.
TABLE 5-1: CONTROL BYTE ADDRESS BITS
Maximum
Devices
Maximum
Contiguous
Address Space
Chip Select Bit Chip Select Bit Chip Select Bit
A2
A1
A0
1K (24C01C)
1K (24XX014)
2K (24C02C)
2K (24XX024/025)
32K (24XX32)
64K (24XX64)
128K (24XX128)
256K (24XX256)
8
8 Kb
A10
A9
A8
8
8 Kb
A10
A9
A8
8
16 Kb
A10
A9
A8
8
16 Kb
A10
A9
A8
8
256 Kb
A14
A13
A12
8
512 Kb
A15
A14
A13
8*
1 Mb
A16*
A15*
A14
8*
2 Mb
A17*
A16*
A15
512K (24XX512)
8
4 Mb
A18
A17
A16
* Up to two 24XX128 or 24XX256 devices in the MSOP package can be added for up to 256 kb or 512 kb of address
space, respectively. Bits A0 and A1 must be set to ‘0’.
© 2007 Microchip Technology Inc.
DS21930B-page 15