参数资料
型号: AD5255BRU25
厂商: ANALOG DEVICES INC
元件分类: 数字电位计
英文描述: 3-Channel Digital Potentiometer with Nonvolatile Memory
中文描述: TRIPLE 25K DIGITAL POTENTIOMETER, INCREMENT/DECREMENT CONTROL INTERFACE, 512 POSITIONS, PDSO24
封装: MO-153AD, TSSOP-24
文件页数: 11/20页
文件大小: 626K
代理商: AD5255BRU25
AD5255
EEPROM INTERFACE
Rev. 0 | Page 11 of 20
MEMORY ADDRESS
MEMORY DATA
MEMORY DATA
S
A
A
A
A
0
E
A
1
E
0
0
0
0
1
1
P
0
0 WRITE
(N BYTES + ACKNOWLEDGE)
EEPROM SLAVE ADDRESS
A/A
Figure 19. EEPROM Write
MEMORY DATA
MEMORY DATA
S
A
A
A
0
E
A
1
E
0
0
0
0
1
1
P
0
1 READ
(N BYTES + ACKNOWLEDGE)
EEPROM SLAVE ADDRESS
A
Figure 20. EEPROM Current Read
SLAVE ADDRESS
MEMORY ADDRESS
S
0 WRITE
A
A
P
0
W
SLAVE ADDRESS
MEMORY DATA
S
R
1 READ
REPEATED START
A
(N BYTES + ACKNOWLEDGE)
A/A
Figure 21. EEPROM Random Read
The 256 bytes of EEPROM memory provided in the AD5255
are organized into 16 pages of 16 bytes each. The word size of
each memory location is one byte wide.
The I
2
C slave address of the EEPROM is 10100(A1E)(A0E),
where A1E and A0E are external pin-programmable address
bits. The 2-pin programmable address bits allow a total of four
AD5255 devices to be controlled by a single I
2
C master bus,
each having its own EEPROM.
An internal 8-bit address counter for the EEPROM is
automatically incremented following each read or write
operation. For read operations, the address counter is
incremented after each byte is read, and the counter rolls over
from Address 255 to 0.
For write operations, the address counter is incremented after
each byte is written. The counter rolls over from the highest
address of the current page to the lowest address of the current
page. For example, writing two bytes beginning at Address 31
causes the counter to roll back to Address 16 after the first byte
is written; then the address increments to 17 after the second
byte is written.
EEPROM Write
Each write operation issued to the EEPROM programs between
1 byte and 16 bytes (1 page) of memory. Figure 19 shows the
EEPROM write interface. The number of bytes of data, N, that
the user wants to send to the EEPROM is unrestricted. If more
than 16 bytes of data are sent in a single write operation, the
address counter rolls back to the beginning address, and the
previously sent data is overwritten.
EEPROM Write-Acknowledge Polling
After each write operation, an internal EEPROM write cycle
begins. During the EEPROM internal write cycle, the I
2
C
interface of the device is disabled. It is necessary to determine if
the internal write cycle is complete and whether the I
2
C
interface is enabled. To do so, execute I
2
C interface polling by
sending a start condition followed by the EEPROM slave
address plus the desired R/W bit. If the AD5255 I
2
C interface
responds with an ACK, the write cycle is complete and the
interface is ready to proceed with further operations. Otherwise,
the I
2
C interface must be polled again to determine whether the
write cycle has been completed.
EEPROM Read
The AD5255 EEPROM provides two different read operations,
shown in Figure 20 and Figure 21. The number of bytes, N, read
from the EEPROM in a single operation is unrestricted. If more
than 256 bytes are read, the address counter rolls back to the
start address, and data previously read is read again.
Figure 20 shows the EEPROM current read operation. This
operation does not allow an address location to be specified,
and reads data beginning at the current address location stored
in the internal address counter.
相关PDF资料
PDF描述
AD5255BRU250 3-Channel Digital Potentiometer with Nonvolatile Memory
AD5255BRU250-RL7 3-Channel Digital Potentiometer with Nonvolatile Memory
AD5255 18 Bit, 1.25MSPS Single Channel Delta-Sigma ADC Single 64-HTQFP -40 to 85
AD5258EVAL2 Nonvolatile, I2C-Compatible 64-Position, Digital Potentiometer
AD5258BRMZ11 Nonvolatile, I2C-Compatible 64-Position, Digital Potentiometer
相关代理商/技术参数
参数描述
AD5255BRU250 制造商:Analog Devices 功能描述:DGTL POTENTIOMETER 512POS 250KOHM TRIPLE 24TSSOP - Rail/Tube
AD5255BRU250-RL7 制造商:Analog Devices 功能描述:DGTL POTENTIOMETER 512POS 250KOHM TRIPLE 24TSSOP - Tape and Reel
AD5255BRU25-RL7 制造商:Analog Devices 功能描述:DGTL POTENTIOMETER 512POS 25KOHM TRIPLE 24TSSOP - Tape and Reel
AD5255BRUZ25 制造商:Analog Devices 功能描述:Digital Potentiometer 512POS 25KOhm Triple 24-Pin TSSOP 制造商:Analog Devices 功能描述:DGTL POTENTIOMETER 512POS 25KOHM TRIPLE 24TSSOP - Rail/Tube 制造商:Analog Devices 功能描述:DIGIPOT I2C NV MEMORY 5K SMD 5255
AD5255BRUZ250 制造商:Analog Devices 功能描述:Digital Potentiometer 512POS 250KOhm Triple 24-Pin TSSOP 制造商:Analog Devices 功能描述:DGTL POTENTIOMETER 512POS 250KOHM TRIPLE 24TSSOP - Rail/Tube 制造商:Analog Devices 功能描述:DIGIPOT I2C NV MEMORY 250K 5255