- 您现在的位置：买卖IC网 > Datasheet目录222 > DS1923-F5# (Maxim Integrated)IBUTTON TEMP/HUMIDITY LOGGER F5 Datasheet资料下载
参数资料
| 型号： | DS1923-F5# |
| 厂商： | Maxim Integrated |
| 文件页数： | 42/55页 |
| 文件大小： | 0K |
| 描述： | IBUTTON TEMP/HUMIDITY LOGGER F5 |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| RoHS指令信息： | IButton RoHS Compliance Plan |
| 标准包装： | 5 |
| 系列： | iButton® |
| 存储容量： | 512B |
| 存储器类型： | NVSRAM（非易失 SRAM） |
| 产品目录页面： | 1431 (CN2011-ZH PDF) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页当前第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页
DS1923
iButton Hygrochron Temperature/Humidity
Logger with 8KB Data-Log Memory
Master-to-Slave
For a write-one time slot, the voltage on the data line
must have crossed the V TH threshold before the write-one
low time t W1LMAX is expired. For a write-zero time slot,
the voltage on the data line must stay below the V TH
threshold until the write-zero low time t W0LMIN is expired.
The voltage on the data line should not exceed V ILMAX
during the entire t W0L or t W1L window. After the V TH
threshold has been crossed, the DS1923 needs a recov-
ery time t REC before it is ready for the next time slot.
Slave-to-Master
A read-data time slot begins like a write-one time slot.
The voltage on the data line must remain below V TL
until the read low time t RL is expired. During the t RL
window, when responding with a 0, the DS1923 starts
pulling the data line low; its internal timing generator
determines when this pulldown ends and the voltage
starts rising again. When responding with a 1, the
DS1923 does not hold the data line low at all, and the
voltage starts rising as soon as t RL is over.
The sum of t RL + δ (rise time) on one side and the inter-
nal timing generator of the DS1923 on the other side
define the master sampling window (t MSRMIN to
t MSRMAX ) in which the master must perform a read from
the data line. For most reliable communication, t RL
should be as short as permissible and the master
should read close to but no later than t MSRMAX . After
reading from the data line, the master must wait until
t SLOT is expired. This guarantees sufficient recovery
time t REC for the DS1923 to get ready for the next time
slot.
Improved Network Behavior
(Switchpoint Hysteresis)
In a 1-Wire environment, line termination is possible
only during transients controlled by the bus master (1-
Wire driver). 1-Wire networks, therefore, are susceptible
to noise of various origins. Depending on the physical
size and topology of the network, reflections from end
points and branch points can add up or cancel each
other to some extent. Such reflections are visible as
glitches or ringing on the 1-Wire communication line.
Noise coupled onto the 1-Wire line from external
42
sources can also result in signal glitching. A glitch dur-
ing the rising edge of a time slot can cause a slave
device to lose synchronization with the master and, as
a consequence, result in a Search ROM command
coming to a dead end or cause a device-specific func-
tion command to abort. For better performance in net-
work applications, the DS1923 uses a new 1-Wire
front-end, which makes it less sensitive to noise and
also reduces the magnitude of noise injected by the
slave device itself.
The DS1923’s 1-Wire front-end differs from traditional
slave devices in four characteristics:
1) The falling edge of the presence pulse has a con-
trolled slew rate. This provides a better match to the
line impedance than a digitally switched transistor,
converting the high-frequency ringing known from
traditional devices into a smoother, low-bandwidth
transition. The slew-rate control is specified by the
parameter t FPD , which has different values for stan-
dard and overdrive speed.
2) There is additional lowpass filtering in the circuit that
detects the falling edge at the beginning of a time
slot. This reduces the sensitivity to high-frequency
noise. This additional filtering does not apply at over-
drive speed.
3) There is a hysteresis at the low-to-high switching
threshold V TH . If a negative glitch crosses V TH but
does not go below V TH - V HY , it is not recognized
(Figure 14, Case A). The hysteresis is effective at
any 1-Wire speed.
4) There is a time window specified by the rising edge
hold-off time t REH during which glitches are ignored,
even if they extend below V TH - V HY threshold
(Figure 14, Case B, t GL < t REH ). Deep voltage
droops or glitches that appear late after crossing the
V TH threshold and extend beyond the t REH window
cannot be filtered out and are taken as the begin-
ning of a new time slot (Figure 14, Case C, t GL ≥
t REH ).
Devices that have the parameters t FPD , V HY , and t REH
specified in their electrical characteristics use the
improved 1-Wire front-end.
Maxim Integrated
相关PDF资料 |
PDF描述 |
|---|---|
| DS1961S-F3# | IBUTTON EEPROM 1KBit F3 |
| DS1963S-F5+ | IBUTTON MONETARY SHA-1 |
| DS1971-F3+ | IBUTTON EEPROM 256KBIT F3 |
| DS1972-F3+ | IBUTTON EEPROM 1KBit F3 |
| DS1973-F3+ | IBUTTON EEPROM 4KBit F3 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| DS1923-F5# | 功能描述:iButton Hygrochron Temp/Hum Logger w/8KB DataLog RoHS:否 存储类型:SRAM 存储容量:512 B 组织: 工作电源电压:3 V to 5.25 V 接口类型:1-Wire 最大工作温度:+ 85 C 尺寸:17.35 mm x 5.89 mm 封装 / 箱体:F5 MicroCan 制造商:Maxim Integrated |
| DS1923-F5#W | 功能描述:iButton Hygrochron Temp/Hum Logger w/8KB DataLog RoHS:否 存储类型:SRAM 存储容量:512 B 组织: 工作电源电压:3 V to 5.25 V 接口类型:1-Wire 最大工作温度:+ 85 C 尺寸:17.35 mm x 5.89 mm 封装 / 箱体:F5 MicroCan 制造商:Maxim Integrated |
| DS1923-F5+ | 功能描述:iButton RoHS:否 存储类型:SRAM 存储容量:512 B 组织: 工作电源电压:3 V to 5.25 V 接口类型:1-Wire 最大工作温度:+ 85 C 尺寸:17.35 mm x 5.89 mm 封装 / 箱体:F5 MicroCan 制造商:Maxim Integrated |
| DS19310 | 制造商:SANYO 制造商全称:Sanyo Semicon Device 功能描述:Color TV Owners Manual Manuel dinstructions du teleouleur Color TV Manual Del Propietario |
| DS193-K | 制造商:Miyama Electric 功能描述: |
发布紧急采购，3分钟左右您将得到回复。