hn58x2408t Renesas Electronics Corporation., hn58x2408t Datasheet - Page 11

• Manufacturer Part Number: hn58x2408t
• Description: Two-wire Serial Interface 2k / 4k / 8k / 16k / 32k / 64k Eeprom 8-kword X 8-bit - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

Acknowledge Timing Waveform
Device Addressing
The EEPROM device requires an 8-bit device address word following a start condition to enable the chip
for a read or a write operation. The device address word consists of 4-bit device code, 3-bit device address
code and 1-bit read/write(R/W) code. The most significant 4-bit of the device address word are used to
distinguish device type and this EEPROM uses “1010” fixed code. The device address word is followed by
the 3-bit device address code in the order of A2, A1, A0. The device address code selects one device out of
all devices which are connected to the bus. This means that the device is selected if the inputted 3-bit
device address code is equal to the corresponding hard-wired A2-A0 pin status. As for the 4kbit, 8kbit and
16kbit EEPROMs, whole or some bits of their device address code may be used as the memory address
bits. For example, A0 is used as a8 of memory address for the 4kbit, A0 and A1 are used as a8 and a9 for
the 8kbit. The 16kbit doesn't use the device address code instead all 3 bits are used as the memory address
bits a8, a9 and a10. The eighth bit of the device address word is the read/write(R/W) bit. A write operation
is initiated if this bit is low and a read operation is initiated if this bit is high. Upon a compare of the device
address word, the EEPROM enters the read or write operation after outputting the zero as an acknowledge.
The EEPROM turns to a stand-by state if the device code is not “1010” or device address code doesn’t
coincide with status of the correspond hard-wired device address pins A0 to A2.
Device Address Word
2k, 32k, 64k 1
4k
8k
16k
Notes: 1. A2 to A0 are device address and a10 to a8 are memory address.
SDA IN
SDA OUT
2. R/W=“1” is read and R/W = “0” is write.
SCL
Device address word (8-bit)
Device code (fixed)
1
1
1
HN58X2402/58X2404/58X2408/58X2416/58X2432/58X2464
0
0
0
0
1
1
1
1
1
0
0
0
0
2
Device address code*
A2
A2
A2
a10
A1
A1
a9
a9
8
1
A0
a8
a8
a8
Acknowledge
out
9
R/W code*
R/W
R/W
R/W
R/W
11
2