- 您现在的位置：买卖IC网 > PDF目录363336 > NM24C05UFLMT8 (FAIRCHILD SEMICONDUCTOR CORP) I2C Serial EEPROM PDF资料下载
参数资料
| 型号： | NM24C05UFLMT8 |
| 厂商： | FAIRCHILD SEMICONDUCTOR CORP |
| 元件分类： | PROM |
| 英文描述： | I2C Serial EEPROM |
| 中文描述： | 512 X 8 I2C/2-WIRE SERIAL EEPROM, PDSO8 |
| 封装： | PLASTIC, TSSOP-8 |
| 文件页数： | 7/13页 |
| 文件大小： | 89K |
| 代理商： | NM24C05UFLMT8 |
7
www.fairchildsemi.com
NM24C04U/NM24C05U Rev. C.1
N
Device Operation Inputs (A1, A2)
Device address pins A1 and A2 are connected to V
CC
or V
SS
to configure the EEPROM chip address.
Table I shows the
active pins.
Table 1.
Device
A0
A1
A2
Effects of Addresses
NM24C04U/05U
x
ADR ADR 2
2
= 4; 4*x (2x2K)** = 16K
*
Max # of devices on bus
** Number of page blocks per density
Under the Standard IIC protocol the maximum density address-
able using the three pin configuration of the IIC protocol is 16K.
Any combination of densities can be used up to this limit.
Background Information (IIC Bus)
As mentioned, the IIC bus allows synchronous bidirectional com-
munication between Transmitter/Receiver using the SCL (clock)
and SDA (Data I/O) lines. All communication must be started with
a valid START condition, concluded with a STOP condition and
acknowledged by the Receiver with an ACKNOWLEDGE condi-
tion.
As shown below, the EEPROMs on the IIC bus may be configured
in any manner required, the total memory addressed can not
exceed 16K (16,384 bits). EEPROM memory address program-
ming is controlled by 2 methods:
Hardware configuring the A1 and A2 pins (Device Address
pins) with pull-up or pull-down to V
CC
or V
SS
.
All unused
pins must be grounded
(tied to V
SS
).
Software addressing the required PAGE BLOCK within the
device memory array (as sent in the Slave Address string).
For devices with densities greater than 16K, a different protocol,
the Extended IIC protocol, is used. Refer to NM24C32U datasheet
(for example) for additional details.
Addressing an EEPROM memory location involves sending a
command
string
with
the
[DEVICE TYPE]
–
[DEVICE ADDRESS]
–
[PAGE BLOCK AD-
DRESS]
–
[BYTE ADDRESS]
DEFINITIONS
following
information:
WORD
8 bits (byte) of data
PAGE
16 sequential addresses (one byte
each) that may be programmed
during a 'Page Write' programming
cycle
PAGE BLOCK
2048 (2K) bits organized into
16
pages of addressable memory.
(8 bits) x (16 bytes) x (16 pages)
= 2048 bits
MASTER
Any IIC device CONTROLLING the
transfer of data (such as a
microprocessor)
SLAVE
Device being controlled
(EEPROMs are always considered
Slaves)
TRANSMITTER
Device currently SENDING data on
the bus (may be either a Master or
Slave).
RECEIVER
Device currently RECEIVING data
on the bus (Master or Slave)
Pin Descriptions
Serial Clock (SCL)
The SCL input is used to clock all data into and out of the device.
Serial Data (SDA)
SDA is a bidirectional pin used to transfer data into and out of the
device. It is an open drain output and may be wire
–
ORed with any
number of open drain or open collector outputs.
WP Write Protection (NM24C05U Only)
If tied to V
CC
, PROGRAM operations onto the upper half of the
memory will not be executed. READ operations are possible. If
tied to V
SS
, normal operation is enabled, READ/WRITE over the
entire memory is possible.
This feature allows the user to assign the upper half of the memory
as ROM which can be protected against accidental programming.
When write is disabled, slave address and word address will be
acknowledged but data will not be acknowledged.
Device Operation
The NM24C04U/05U supports a bidirectional bus oriented proto-
col. The protocol defines any device that sends data onto the bus
as a transmitter and the receiving device as the receiver. The
device controlling the transfer is the master and the device that is
controlled is the slave. The master will always initiate data
transfers and provide the clock for both transmit and receive
operations. Therefore, the NM24C04U/05U will be considered a
slave in all applications.
Clock and Data Conventions
Data states on the SDA line can change only during SCL LOW.
SDA state changes during SCL HIGH are reserved for indicating
start and stop conditions. Refer to Figure 2 and Figure 3 on next
page.
Start Condition
All commands are preceded by the start condition, which is a
HIGH to LOW transition of SDA when SCL is HIGH. The
NM24C04U/05U continuously monitors the SDA and SCL lines for
the start condition and will not respond to any command until this
condition has been met.
Stop Condition
All communications are terminated by a stop condition, which is a
LOW to HIGH transition of SDA when SCL is HIGH. The stop
condition is also used by the NM24C04U/05U to place the device
in the standby power mode.
Write Cycle Timing
Acknowledge
Acknowledge is a hardware convention used to indicate success-
ful data transfers. The transmitting device, either master or slave,
will release the bus after transmitting eight bits.
During the ninth clock cycle the receiver will pull the SDA line to
LOW to acknowledge that it received the eight bits of data. Refer
to Figure 4.
相关PDF资料 |
PDF描述 |
|---|---|
| NM24C05UFLN | I2C Serial EEPROM |
| NM24C05UFLVM8 | I2C Serial EEPROM |
| NM24C05UFLVMT8 | I2C Serial EEPROM |
| NM24C05UFLVN | I2C Serial EEPROM |
| NM24C05UFLZEM8 | I2C Serial EEPROM |
相关代理商/技术参数 |
参数描述 |
|---|---|
| NM24C05UFLN | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:I2C Serial EEPROM |
| NM24C05UFLVM8 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:I2C Serial EEPROM |
| NM24C05UFLVMT8 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:I2C Serial EEPROM |
| NM24C05UFLVN | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:I2C Serial EEPROM |
| NM24C05UFLZEM8 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:I2C Serial EEPROM |
发布紧急采购，3分钟左右您将得到回复。