AT24C32D 데이터 시트보기 (PDF) - Atmel Corporation
부품명
상세내역
제조사
AT24C32D Datasheet PDF : 24 Pages
| |||
7. Device Addressing
The 32K EEPROM requires an 8-bit device address word following a Start condition to enable the chip for a
Read or Write operation. The device address word consists of a mandatory ‘1010’ sequence for the first four
most significant bits which is known as the device type identifier. These four bits are bit 7, bit 6, bit 5, and bit 4 as
seen in Figure 7-1. This is common to all 2-wire Serial EEPROM devices.
The next three bits are the A2, A1, and A0 hardware address select bits which allow as many as eight devices
on the same bus. These bits must compare to their corresponding hard wired input pins, A2, A1, and A0. The A2,
A1, and A0 pins use an internal proprietary circuit that biases them to a logic low condition if the pins are allowed
to float.
When utilizing the 5-ball WLCSP or the 5-lead SOT-23 packages, the A2, A1, and A0 pins are not available. The
A2, A1, and A0 pins are internally pulled to ground and thus the A2, A1, and A0 device address bits must always
be set to a Logic 0 to communicate with the device. This condition is depicted in Figure 7-1 below.
The eighth bit of the device address is the Read/write operation select bit. A Read operation is initiated if this bit
is a Logic 1, and a Write operation is initiated if this bit is a Logic 0.
Upon a successful comparison of the device address, the EEPROM will output a zero during the following clock
cycle. If a compare is not made, the device will not acknowledge and will instead return to a standby state.
Figure 7-1. Device Addressing
Package
SOIC, TSSOP, UDFN,
XDFN, and VFBGA
Bit 7
Device Type Identifier
Bit 6
Bit 5
Bit 4
1
0
1
0
Hardware Address Select Bits
Bit 3
Bit 2
Bit 1
R/W Select
Bit 0
A2
A1
A0
R/W
SOT-23 and WLCSP
1
0
1
0
0
0
0
R/W
MSB
LSB
Data Security: The AT24C32D has a hardware data protection scheme that allows the user to write protect the
whole memory when the WP pin is at VCC.
AT24C32D [DATASHEET]
9
Atmel-8866D-SEEPROM-AT24C32D-Datasheet_122016
Share Link: 