ST意法半导体
直播中

宣苗

7年用户 184经验值
私信 关注
[问答]

LPS25HB温度补偿行为是什么

我和我的同事正在评估LPS25HB并遇到了一些我们不理解的行为。我们现在正试图解决两个问题:

嵌入式温度补偿行为令人困惑。准确性不是它应该是什么。具体:

在我们的一个数据记录(pressureLog_25Hz.xlsx)中,我们看到绝对压力跟踪温度。我们预计温度会发生变化,但不是绝对压力。绝对压力以约3hPa / C的速率变化。嵌入式温度补偿不应该与此相关吗?在我们在汽车中进行的测试(汽车压力log.xlsx)中,我们看到温度下降然后增加,但如果您通过数据绘制趋势线,压力几乎是恒定的。这次嵌入式温度补偿似乎正在做些什么。我们需要帮助确定传感器为什么表现不同。该部件的数据表声称在20到60℃之间的绝对精度为+/- 0.2 hPa。到目前为止,我们从传感器获取的数据不符合规范。例如,我最近的测试,我们当地的气象站报告的海平面压力为1016.2毫巴.LPS25HB评估套件告诉我们绝对压力为1026.5毫巴。我们海拔约160,相当于压力差-6毫巴,所以LPS25HB应报告约1010毫巴。这是16.5毫巴!谢谢您的帮助!

#lps25hb

以上来自于谷歌翻译


以下为原文




My colleagues and I are evaluating the LPS25HB and came across some behavior we don't understand. There are two issues we are trying to resolve right now:


  • Embedded temperature compensation behavior is confusing.
  • Accuracy isn't what it should be.
Specifics:


  • In one of our datalogs (pressureLog_25Hz.xlsx) we see absolute pressure tracking with temperature. We expected temperature to change, but not absolute pressure. Absolute pressure is changing at a rate of about 3 hPa/C. Shouldn't the embedded temperature compensation deal with this?
  • In a test we did in a car (car pressure log.xlsx), we saw temperature drop and then increase, but the pressure is almost constant if you draw a trend line through the data. It seems like embedded temperature compensation is doing something this time.
    • We need help determining why is the sensor acting differently.
  • The datasheet for the part claims an absolute accuracy of +/-0.2 hPa between 20 and 60 C. So far, the data we have taken from the sensor does not meet the spec. For example,
    • I a recent test, our local weather stations reported a sea level pressure of 1016.2 mbar.
    • The LPS25HB evaluation kit is told us the absolute pressure was 1026.5 mbar.
    • We are about 160 above sea level, which equates to a pressure difference of -6 mbar, so the LPS25HB should have reported about 1010 mbar. It was off by 16.5 mbar!

Thanks for the help!
  
#lps25hb

回帖(4)

李代三

2018-9-21 16:58:37
嗨,
我需要有关您的测试的更多信息,1。pressureLog_25Hz和2 .car压力日志。
 
 我认为在这两种情况下都没有控制环境。你可否确认?
 我会知道两种情况下使用的设置。
 它们是一样的吗?
 ODR的价值是多少?温度和压力的内部平均值是多少?是否启用了嵌入式过滤?在第一种情况下,如果环境不受控制,为什么你会期望温度变化,而不是压力?
我还需要知道用于测试的电压值是多少。
问候
 
 安东内拉
我和我的同事正在评估LPS25HB并遇到了一些我们不理解的行为。我们现在正试图解决两个问题:
 
 嵌入式温度补偿行为令人困惑。准确性不是应该的.Specifics:
 
 在我们的一个数据记录(pressureLog_25Hz.xlsx)中,我们看到绝对压力跟踪温度。我们预计温度会发生变化,但不是绝对压力。绝对压力以约3hPa / C的速率变化。嵌入式温度补偿不应该处理这个吗?在我们在汽车(汽车压力log.xlsx)中进行的测试中,我们看到温度下降然后增加,但是如果您在数据中绘制趋势线,则压力几乎是恒定的。这次嵌入式温度补偿似乎正在做些什么。我们需要帮助确定传感器为什么表现不同。该部件的数据表声称在20到60℃之间的绝对精度为+/- 0.2 hPa。到目前为止,我们从传感器获取的数据不符合规范。例如,我最近的测试,我们当地的气象站报告的海平面压力为1016.2毫巴。 LPS25HB评估套件告诉我们绝对压力为1026.5毫巴。我们海拔约160,相当于-6毫巴的压力差,因此LPS25HB应报告约1010毫巴。这是16.5毫巴!谢谢您的帮助!

以上来自于谷歌翻译


以下为原文







Hi,
I need further information about your test, 1. pressureLog_25Hz and 2 .car pressure log.

I suppose in both cases the environment was not controlled. Can you confirm?
I would know the settings used in both cases.
Are they the same?
What is the value of ODR? What internal average for temperature and pressure? Was the embedded filtering enabled?In the first case, if the environment is not controlled, why do you expect that temperature changes, but not the pressure?
I need to know what is the value of voltage supply used for your test too.
Regards

Antonella
My colleagues and I are evaluating the LPS25HB and came across some behavior we don't understand. There are two issues we are trying to resolve right now:



  • Embedded temperature compensation behavior is confusing.
  • Accuracy isn't what it should be.
Specifics:



  • In one of our datalogs (pressureLog_25Hz.xlsx) we see absolute pressure tracking with temperature. We expected temperature to change, but not absolute pressure. Absolute pressure is changing at a rate of about 3 hPa/C. Shouldn't the embedded temperature compensation deal with this?
  • In a test we did in a car (car pressure log.xlsx), we saw temperature drop and then increase, but the pressure is almost constant if you draw a trend line through the data. It seems like embedded temperature compensation is doing something this time.

    • We need help determining why is the sensor acting differently.

  • The datasheet for the part claims an absolute accuracy of +/-0.2 hPa between 20 and 60 C. So far, the data we have taken from the sensor does not meet the spec. For example,  

    • I a recent test, our local weather stations reported a sea level pressure of 1016.2 mbar.
    • The LPS25HB evaluation kit is told us the absolute pressure was 1026.5 mbar.
    • We are about 160 above sea level, which equates to a pressure difference of -6 mbar, so the LPS25HB should have reported about 1010 mbar. It was off by 16.5 mbar!

Thanks for the help!
举报

宣苗

2018-9-21 17:08:21
嗨Antonella,
 
 
谢谢你的提问。我们没有在我们控制压力的环境中进行测试,但是,我们在外面进行测试,并将我们正在阅读的压力与附近主要机场的可靠系统进行实时比较。
 
设置明智,我们使用评估板和ST软件之一。更多细节:
易于配置(电源模式 - 活动,数据速率 - 25 Hz,BDU - 启用,压力分辨率 - 平均512,温度分辨率 - 平均64,嵌入式过滤器 - 禁用)。
所有测试都使用Easy Config。所有测试均由同一台笔记本电脑/ USB线供电。
 
短剑的一种
 
附:有没有办法私人给你发消息?william hill官网 回复和编辑工具真的很糟糕。

以上来自于谷歌翻译


以下为原文





Hi Antonella,


Thank you for the questions. We were not testing in an environment where we controlled for pressure, however, we were testing outside and comparing the pressure we were reading against a reliable system at a nearby major airport in real time.

Settings wise, we were using one of the evaluation boards and the ST software. More details:
Easy Configuration (Power Mode - Active, Data Rate - 25 Hz, BDU - Enabled, Pressure Resolution - Avg 512, Temp resolution - Avg 64, Embedded Filter - Disabled).
All tests use Easy Config. All tests powered by the same laptop/USB cable.

Kris

P.S. is there a way to private message you about this? The forum reply and editing tools are really awful.
举报

李代三

2018-9-21 17:23:14
嗨克里斯,
 
 感谢您的回复。
 关于第一次测试,如果环境不受控制,压力和温度的趋势并不奇怪。
 传感器受到环境变化的影响,压力和温度随着这些变化而增加,在45分钟内(从execel文件中报告的7.44 AM到08.21 AM)。在第二次测试中,温度下降低于0.5°C大约1分钟,所以对读取压力的影响很小。
关于准确性,请记住,数据表中报告的值是指未焊接的样品。
 
 您必须考虑焊接后的偏移应在0-3mbar(工作电压为1.8 V)和大于3 mbar的工作电压大于1.8V时工作。当然16,5 mbar过大。
 
 你能用另一个样品/设备重复相同的测量,并检查测量/误差是否可以重复吗?问候
 
 安东内拉

以上来自于谷歌翻译


以下为原文







Hi Kris,

thanks for reply.
Concerning the first test, the trend of pressure and temperature is not strange if the environment is not controlled.
The sensor is affected from of environmental changes and the pressure and temperature follow these changes increasing in 45 minutes (from 7.44 AM to 08.21 AM as reported in execel file).In the second test, the drop in temperature is less  0.5 °C in about 1 minute,so the influence on the read pressure is very little.
Concerning the accuracy, you keep in mind that the value reported in the datasheet is refered to the sample not soldered.

You have to consider that there is an offset after soldering that should be in the range 0-3mbar ( working at 1.8 V) and greater than 3 mbar working with voltages greater than 1.8V.Of course 16,5 mbar is too excessive.

Can you repeat the same measurement  with another sample/device and to check if the measurement/error is repetible?Regards

Antonella
举报

夏房釜

2018-9-21 17:41:58
你好
 
 
 我可能有点迟到回复这个帖子,但我附上了一个16通道传感器的校准数据,我们使用16个LPH25设备设计。该装置已在20至60度,72000Pa至126000Pa的烘箱中校准。
 
 数据显示每个通道的测试压力,以及不同温度下每个通道的记录值。通常我们会在每个传感器上看到几百帕斯卡的偏移,当温度从20度变化到60度时,增益的变化会产生150Pa的额外误差。
 
 问候

以上来自于谷歌翻译


以下为原文





Hi


I might be a bit late replying to this thread, but I enclose some calibration data from a 16 channel sensor we have designed using 16 off LPH25 devices. The unit has been calibrated in an oven at 20 to 60 degrees, between 72000Pa and 126000Pa.

The data shows the test pressure for each channel, and the recorded value for each channel at the different temperatures. Typically we see an offset of several hundred Pascals on each sensors, and a change in gain giving an additional error of 150Pa as temperature changes from 20 degrees to 60 degrees.

Regards
举报

更多回帖

发帖
×
20
完善资料,
赚取积分