参数资料
型号: DS2505P/T&R
厂商: Maxim Integrated
文件页数: 15/24页
文件大小: 0K
描述: IC OTP 16KBIT 6TSOC
标准包装: 4,000
格式 - 存储器: EPROMs
存储器类型: EPROM OTP
存储容量: 16K(16K x 1)
接口: 1 线 串行
工作温度: -40°C ~ 85°C
封装/外壳: 6-LSOJ
供应商设备封装: 6-TSOC
包装: 带卷 (TR)

DS2505
Hardware Configuration
The 1-Wire bus has only a single line by definition; it is important that each device on the bus be able to
drive it at the appropriate time. To facilitate this, each device attached to the 1-Wire bus must have an
open drain connection or 3-state outputs. The DS2505 is an open drain part with an internal circuit
equivalent to that shown in Figure 6. The bus master can be the same equivalent circuit. If a bi-
directional pin is not available, separate output and input pins can be tied together.
The bus master requires a pullup resistor at the master end of the bus, with the bus master circuit
equivalent to the one shown in Figures 7a and 7b. The value of the pullup resistor should be
approximately 5 k ? for short line lengths.
A multidrop bus consists of a 1-Wire bus with multiple slaves attached. The 1-Wire bus has a maximum
data rate of 16.3 kbits per second. If the bus master is also required to perform programming of the
EPROM portions of the DS2505, a programming supply capable of delivering up to 10 milliamps at
12 volts for 480 μs is required. 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 120 μs, one or more of the devices on the bus may be
reset.
Transaction Sequence
The sequence for accessing the DS2505 via the 1-Wire port is as follows:
?
?
?
?
Initialization
ROM Function Command
Memory Function Command
Read/Write Memory/Status
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 a presence pulse(s) transmitted by the
slave(s).
The presence pulse lets the bus master know that the DS2505 is on the bus and is ready to operate. For
more details, see the “1-Wire Signaling” section.
ROM FUNCTION COMMANDS
Once the bus master has detected a presence, it can issue one of the four ROM function commands. All
ROM function commands are 8 bits long. A list of these commands follows (refer to flowchart in
Figure 8):
Read ROM [33H]
This command allows the bus master to read the DS2505’s 8-bit family code, unique 48–bit serial
number, and 8-bit CRC. This command can be used only if there is a single DS2505 on the bus. If more
than one slave is present on the bus, a data collision will occur when all slaves try to transmit at the same
time (open drain will produce a wired-AND result).
15 of 24
相关PDF资料
PDF描述
GJM0335C1E1R2CB01D CAP CER 1.2PF 25V NP0 0201
AM3XF5 BATTERY PK 7.5V AA SIZE ALKALINE
EMM36DTAN-S189 CONN EDGECARD 72POS R/A .156 SLD
5747238-6 CONN D-SUB PLUG R/A 25POS
T97Z476K050CSA CAP TANT 47UF 50V 10% 3024
相关代理商/技术参数
参数描述
DS2505P-UNW 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:UniqueWare Add-Only Memory
DS2505P-UNW-1154 制造商:Maxim Integrated Products 功能描述:
DS2505P-UNW-PPPP 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:UniqueWare Add-Only Memory
DS2505T 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:16-kbit Add-Only Memory
DS2505TR 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:16-kbit Add-Only Memory