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杨丽

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[问答]

如何使用校准寄存器?

我们正在评估LPS25HB BP传感器,并有几个问题。我注意到有几个william hill官网 成员提出了类似的问题,但未收到回复。我真的很感激答案,因为这表明LPS25HB不是一种“孤儿”,不受支持的产品。
1)数据表提到了对BP的焊接效果,并说可以使用寄存器来存储单点校准。数据表中没有关于此的任何其他细节。我们发现我们测试的样品中存在大量(~0.5 kPa +)压力不准确度。这是预期的吗?究竟我们如何使用校准寄存器?它是如何计算的?同样,这些对任何用户都是重要的,数据表没有提供有意义的信息。
2)我们注意到对BP的温度影响很大。看来芯片内部没有进行温度补偿,尽管数据表提到了二次温度补偿,并声称20-60C的变化只会导致20 Pa(0.2 hPa)的变化。我看到,从~5℃的环境温度变化幅度或更大,实际环境BP没有显着变化。是否需要打开内部温度补偿?或者由用户决定经验温度校准?
我们将非常感谢这些问题的答案,并将帮助我们评估LPS25HB相对于其他制造商生产的竞争传感器。

#lps25hb

以上来自于谷歌翻译


以下为原文




We are evaluating the LPS25HB BP sensor, and have a couple of questions. I notice that several forum members have asked similar questions, but without receiving a reply. I would really appreciate an answer, as this would indicate that the LPS25HB is not an 'orphan', unsupported product.
1) The datasheet mentions a soldering effect on BP, and says that a register is available to store a one-point calibration. There are no other details at all about this in the datasheet. We have found substantial (~0.5 kPa+) pressure inaccuracy in samples we have tested. Is this to be expected? Exactly how are we to use the calibration register? How is it calculated? Again, these are important points for any user, and the datasheet gives no meaningful information.
2) We notice a very substantial temperature effect on BP. It appears that no temperature compensation is being done internally to the chip, although the datasheet mentions quadratic temperature compensation, and claims that a 20-60C change will cause only a 20 Pa (0.2 hPa) change. I see that magnitude of change or greater from a ~5C ambient temperature change with no significant change in actual ambient BP. Does internal temperature compensation need to be turned on? Or is it up to the user to determine an empirical temperature calibration?
Answers to these questions would be greatly appreciated and will help us to evaluate the LPS25HB relative to competitive sensors made by other manufacturers.

#lps25hb

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曾玲娟

2019-5-16 11:08:02
通过填写RPDS_L和RPDS_H寄存器可以应用单点校准(参见数据手册中的第8.22和8.23章)。它基本上是从输出值中减去的偏移量。它是16位值,具有16个最高有效位的输出值。焊接和/或清洁过程可能导致压力不准确0.5kPa = 5hPa。它可以通过上面提到的单点校准进行补偿。内部温度补偿始终打开,您无需打开它。绝对的压力
数据表中提到的温度精度是典型值。不保证最大/最小值。

以上来自于谷歌翻译


以下为原文





  • One-point calibration can by applied by filling in RPDS_L and RPDS_H registers (see chapter 8.22 and 8.23 in datasheet). It is basically offset which is subtracted from the output value. It is 16-bit value with weight of 16 most significant bits of output value.


  • Pressure inaccuracy 0.5kPa = 5hPa can be caused by soldering and/or cleaning process. It can be compensated by the one-point calibration mentioned above.
  • Internal temperature compensation is always on, you don't have to switch it on. Absolute pressure
    accuracy over temperature mentioned in the datasheet is typical value. Max/Min value is not guaranteed.
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曾玲娟

2019-5-16 11:27:42
根据我们的经验,焊接工艺可以产生偏移,但灵敏度不受影响。整个范围的偏移量相同。
由于这个原因,传感器只需要添加剂校正和可用。

以上来自于谷歌翻译


以下为原文




From our experience soldering process can create an offset but the sensitivity is not influenced. The offset is the same for whole range.
From that reason only additive correction is needed and available in the sensor.
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