- 您现在的位置：买卖IC网 > PDF目录19365 > DS18B20Z+T&R (Maxim Integrated)IC THERM MICROLAN PROG-RES 8SOIC PDF资料下载
参数资料
| 型号： | DS18B20Z+T&R |
| 厂商： | Maxim Integrated |
| 文件页数： | 8/22页 |
| 文件大小： | 528K |
| 描述： | IC THERM MICROLAN PROG-RES 8SOIC |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 功能： | 温度计，恒温计 |
| 传感器类型： | 内部 |
| 感应温度： | -55°C ~ 125°C |
| 精确度： | ±2°C（最小值） |
| 拓扑： | 寄存器库，变签式暂存器 |
| 输出类型： | 1-Wire? |
| 输出警报： | 是 |
| 输出风扇： | 无 |
| 电源电压： | 3 V ~ 5.5 V |
| 工作温度： | -55°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 供应商设备封装： | 8-SOIC |
| 包装： | 带卷 (TR) |
DS18B20
8 of 22
CONFIGURATION REGISTER
Byte 4 of the scratchpad memory contains the configuration register, which is organized as illustrated in
Figure 8. The user can set the conversion resolution of the DS18B20 using the R0 and R1 bits in this
register as shown in Table 2. The power-up default of these bits is R0 = 1 and R1 = 1 (12-bit resolution).
Note that there is a direct tradeoff between resolution and conversion time. Bit 7 and bits 0 to 4 in the
configuration register are reserved for internal use by the device and cannot be overwritten.
Figure 8. Configuration Register
BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0
0
R1
R0
1
1
1
1
1
Table 2. Thermometer Resolution Configuration
R1
R0
RESOLUTION
(BITS)
MAX CONVERSION
TIME
0
0
9
93.75ms
(t
CONV
/8)
0
1
10
187.5ms
(t
CONV
/4)
1
0
11
375ms
(t
CONV
/2)
1
1
12
750ms
(t
CONV
)
CRC GENERATION
CRC bytes are provided as part of the DS18B20s 64-bit ROM code and in the 9
th
byte of the scratchpad
memory. The ROM code CRC is calculated from the first 56 bits of the ROM code and is contained in the
most significant byte of the ROM. The scratchpad CRC is calculated from the data stored in the
scratchpad, and therefore it changes when the data in the scratchpad changes. The CRCs provide the bus
master with a method of data validation when data is read from the DS18B20. To verify that data has
been read correctly, the bus master must re-calculate the CRC from the received data and then compare
this value to either the ROM code CRC (for ROM reads) or to the scratchpad CRC (for scratchpad reads).
If the calculated CRC matches the read CRC, the data has been received error free. The comparison of
CRC values and the decision to continue with an operation are determined entirely by the bus master.
There is no circuitry inside the DS18B20 that prevents a command sequence from proceeding if the
DS18B20 CRC (ROM or scratchpad) does not match the value generated by the bus master.
The equivalent polynomial function of the CRC (ROM or scratchpad) is:
CRC = X
8
+ X
5
+ X
4
+ 1
The bus master can re-calculate the CRC and compare it to the CRC values from the DS18B20 using the
polynomial generator shown in Figure 9. This circuit consists of a shift register and XOR gates, and the
shift register bits are initialized to 0. Starting with the least significant bit of the ROM code or the least
significant bit of byte 0 in the scratchpad, one bit at a time should shifted into the shift register. After
shifting in the 56th bit from the ROM or the most significant bit of byte 7 from the scratchpad, the
polynomial generator will contain the re-calculated CRC. Next, the 8-bit ROM code or scratchpad CRC
from the DS18B20 must be shifted into the circuit. At this point, if the re-calculated CRC was correct, the
shift register will contain all 0s. Additional information about the Maxim 1-Wire cyclic redundancy check
相关PDF资料 |
PDF描述 |
|---|---|
| 1N5402RLG | DIODE STD REC 3A 200V DO201AD |
| VJ1206A100KBEAT4X | CAP CER 10PF 500V 10% NP0 1206 |
| EBC19DRTI-S13 | CONN EDGECARD 38POS .100 EXTEND |
| AIMC-0201-1N5S-T | INDUCTOR MULTILAYER 1.5NH 0201 |
| IR2521DSTRPBF | IC BALLAST CTLR ADAPTIVE 8-SOIC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| DS18B20Z-W | 制造商:Maxim Integrated Products 功能描述: |
| DS18S20 | 功能描述:板上安装温度传感器 RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor |
| DS18S20/T&R | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述:IC THERM MICROLAN HI PREC TO-92 |
| DS18S20/T&R | 功能描述:板上安装温度传感器 RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor |
| DS18S20+ | 功能描述:板上安装温度传感器 Prgmble Resolution 1-Wire Parasite Pwr RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor |
发布紧急采购，3分钟左右您将得到回复。