参数资料
型号: DS28EC20+T
厂商: Maxim Integrated Products
文件页数: 17/27页
文件大小: 0K
描述: IC EEPROM 20KBIT TO92-3
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 2,000
格式 - 存储器: EEPROMs - 串行
存储器类型: EEPROM
存储容量: 20K(256 x 80)
接口: 1 线 串行
工作温度: -40°C ~ 85°C
封装/外壳: TO-226-3、TO-92-3(TO-226AA)成形引线
供应商设备封装: TO-92-3
包装: 带卷 (TR)
DS28EC20: 20Kb 1-Wire EEPROM
speed, the DS28EC20 requires V PUP to be 5V ±5%. Note that legacy 1-Wire products support a standard
communication speed of 16.3kbps and overdrive of 142kbps. The slightly reduced rates for the DS28EC20 are a
result of additional recovery times, which in turn were driven by a 1-Wire physical interface enhancement to
improve noise immunity. The value of the pullup resistor primarily depends on the network size and load conditions.
The DS28EC20 requires a pullup resistor of 2.2k ? (max) at any speed.
The idle state for the 1-Wire bus is high. If for any reason a transaction needs to be suspended, the bus MUST be
left in the idle state if the transaction is to resume. If this does not occur and the bus is left low for more than 16μs
(overdrive speed) or more than 120μs (standard speed), one or more devices on the bus can be reset.
Figure 8. Hardware Configuration
BUS MASTER
V PUP
R PUP
DS28EC20 1-Wire PORT
RX
DATA
RX
TX
Open-Drain
Port Pin
RX = RECEIVE
TX = TRANSMIT
I L
100 ?
MOSFET
TX
TRANSACTION SEQUENCE
The protocol for accessing the DS28EC20 through the 1-Wire port is as follows:
?
?
?
?
Initialization
ROM Function Command
Memory Function Command
Transaction/Data
INITIALIZATION
All transactions on the 1-Wire bus begin with an initialization sequence. The initialization sequence consists of a
reset pulse transmitted by the bus master followed by presence pulse(s) transmitted by the slave(s). The presence
pulse lets the bus master know that the DS28EC20 is on the bus and is ready to operate. For more details, see the
1-Wire Signaling section.
1-Wire ROM FUNCTION COMMANDS
Once the bus master has detected a presence, it can issue one of the seven ROM function commands that the
DS28EC20 supports. All ROM function commands are 8 bits long. See Figure 9 for list of these commands.
READ ROM [33h]
This command allows the bus master to read the DS28EC20’s 8-bit family code, unique 48-bit serial number, and
8-bit CRC. This command can only be used if there is a single slave on the bus. If more than one slave is present
on the bus, a data collision occurs when all slaves try to transmit at the same time (open drain produces a wired-
AND result). The resultant family code and 48-bit serial number result in a mismatch of the CRC.
17 of 27
相关PDF资料
PDF描述
DS301X KWIK-CHG DESIGNATION STRIP SGL
DS3030W-100# IC NVSRAM 256KBIT 100NS 256BGA
DS3045W-100# IC NVSRAM 1MBIT 100NS 256BGA
DS3050W-100# IC NVSRAM 4MBIT 100NS 256BGA
DS3065W-100# IC NVSRAM 8MBIT 100NS 256BGA
相关代理商/技术参数
参数描述
DS28EL15 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:DeepCover Secure Authenticator with 1-Wire SHA-256 and 512-Bit User EEPROM
DS28EL15Q+T 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:DeepCover Secure Authenticator with 1-Wire SHA-256 and 512-Bit User EEPROM
DS28EL25 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:DeepCover Secure Authenticator with 1-Wire SHA-256 with 4Kb User EEPROM
DS28EL25Q+T 制造商:Maxim Integrated Products 功能描述:1-WIRE 1.8V 4KB EEPROM WITH SHA-256 TDFN T&R - Tape and Reel
DS28-L147-203 制造商:CONEXANT 制造商全称:CONEXANT 功能描述:SmartV.XX Modem