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参数资料
| 型号： | MAX6682MUA+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 6/9页 |
| 文件大小： | 0K |
| 描述： | IC THERMISTOR TO DGTL 8UMAX |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 类型： | 温度传感器 |
| 输入类型： | 逻辑 |
| 输出类型： | 逻辑 |
| 接口： | 3 线 SPI 串行 |
| 电流 - 电源： | 29µA |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-TSSOP，8-MSOP（0.118"，3.00mm 宽） |
| 供应商设备封装： | 8-uMAX |
| 包装： | 带卷 (TR) |
MAX6682
NTC thermistors are often described by the resistance
at +25°C. Therefore, a 10k
thermistor has a resistance
of 10k
at +25°C. When choosing a thermistor, ensure
that the thermistor’s minimum resistance (which occurs
at the maximum expected operating temperature) in
series with REXT does not cause the voltage reference
output current to exceed about 1mA. Some standard
10k
thermistors with similar characteristics are listed
in Table 2. When used with one of these thermistors
and the recommended series resistor, the MAX6682
provides output data scaled in °C over the +10°C to
+40°C temperature range.
Choosing the External Resistor
Choose REXT to minimize nonlinearity errors from the
thermistor:
1) Decide on the temperature range of interest (for
example 0°C to +70°C).
2) Find the thermistor values at the limits of the tem-
perature range. RMIN is the minimum thermistor
value (at the maximum temperature) and RMAX is
the maximum thermistor value (at the minimum tem-
perature). Also find RMID, the thermistor resistance
in the middle of the temperature range (+35°C for
the 0°C to +70°C range).
3) Find REXT using the equation below:
Table 3 shows nominal output data for several tempera-
tures when REXT has been chosen according to the
equation above for a temperature range of 0°C to
+70°C. The output data is not conveniently scaled to
the actual temperature over this range, but the linearity
is better than 2.4°C over the 0°C to +70°C range
(Figure 2). The temperature weighting over this range is
0.14925°C/LSB.
Serial Interface
The Typical Application Circuit shows the MAX6682
interfaced with a microcontroller. In this example, the
MAX6682 processes the reading from REXT and trans-
mits the data through an SPI-compatible interface.
Force CS low and apply a clock signal at SCK to read
the results at SO. Forcing CS low immediately stops
any conversion in process. Initiate a new conversion by
forcing CS high.
Force CS low to output the first bit on the SO pin. A
complete read requires 11 clock cycles. Read the 11
output bits on the rising edge of the clock, if the first bit
D10 is the sign bit. Bits D10–D0 contain the converted
temperature in the order of MSB to LSB.
After the 11th clock cycle, SO goes to a high-imped-
ance state. SO remains high impedance until CS is
pulsed high and brought back low. Figure 4 is the SO
output.
Power-Supply Considerations
The MAX6682 accuracy is relatively unaffected by
power-supply coupled noise. In most applications,
bypass VCC to GND by placing a 0.1F ceramic
bypass capacitor close to the supply pin of the
devices.
Thermal Considerations
Self-heating degrades the temperature measurement
accuracy of thermistors. The amount of self-heating
depends on the power dissipated in the thermistor and
the dissipation constant of the thermistor. Dissipation
constants depend on the thermistor’s package and can
vary considerably.
A typical thermistor might have a dissipation constant
equal to 1mW/°C. For every mW the thermistor dissi-
pates, its temperature rises by 1°C. For example, con-
R
RR
R
RR
R
EXT
MID
MIN
MAX
MIN MAX
MIN
MAX
MID
=
+
()
+
2
Thermistor-to-Digital Converter
6
_______________________________________________________________________________________
-0.25
-0.15
-0.20
-0.05
-0.10
0.05
0
0.10
0.20
0.15
0.25
0
101520
5
2530354045
THERMISTOR NONLINEARITY
vs. TEMPERATURE
TEMPERATURE (°C)
LINEARITY
ERROR
(
°C)
Figure 3. Thermistor Nonlinearity vs. Temperature for a Standard
Thermistor from +10°C to +40°C
Figure 4. SO Output
10-BIT TEMPERATURE READING
Bit
10
98
7654
321
0
MSB
(Sign)
LSB
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相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX6683AUB | 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 |
| MAX6683AUB+ | 功能描述:板上安装温度传感器 Temperature Sensor & System Monitor 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 |
| MAX6683AUB+T | 功能描述:板上安装温度传感器 Temperature Sensor & System Monitor 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 |
| MAX6683AUB-T | 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 |
| MAX6683EVKIT | 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 |
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