<p><span>作者：</span><strong>Chris Murphy</strong></p>
<p><strong>问题：</strong></p>
<p><span>我的消费级加速度计理论上可以测量小于1°的倾斜。在温度变化及振动条件下是否仍然可以实现这样的测量精度？</span></p>
<p><strong>答案：</strong></p>
<p><span>答案很可能是否定的。关于明确倾斜精度值的问题总是很难回答，因为在MEMS传感器性能方面需要考虑许多环境因素。通常，消费级加速度计难以在动态环境中检测小于1°的倾斜。为了表明这一点，我们将通用消费级加速度计与新一代低噪声、低漂移和低功耗MEMS加速度计进行比较。这一比较着眼于倾斜应用中存在的许多误差源，以及可以补偿或消除哪些误差。</span></p>
<p><span>可以观察到0<span> </span></span><em>g</em><span>偏置精度、焊接引起的0<span> </span></span><em>g</em><span>偏置漂移、PCB外壳对准引起的0<span> </span></span><em>g</em><span>偏置漂移、0<span> </span></span><em>g</em><span>偏置温度系数、灵敏准确度和温度系数、非线性度以及横轴灵敏度等误差，并且可以通过装配后校准流程减少这些误差。滞后、使用寿命期间的0<span> </span></span><em>g</em><span>偏置漂移、使用寿命期间的灵敏度漂移、潮湿引起的0<span> </span></span><em>g</em><span>漂移以及温度随时间变化引起的PCB弯曲和扭转等等，这些误差项无法通过校准或其他方法解决，需要通过一定程度的原位维修才能减少。在这一比较中，假设横轴灵敏度、非线性度和灵敏度得到补偿，因为相比温度系数失调漂移和振动校正，尽量减少这些误差所需的工作量要少得多。</span></p>
<p><span>表1列出了消费级</span><span>ADXL345</span><span>加速度计理想性能规格及相应倾斜误差的估算值。试图达到最佳倾斜精度时，必须采用某种形式的温度稳定或补偿。在下面的例子中，假设恒温为25℃。无法完全补偿的最主要误差促成因素是温漂失调、偏置漂移和噪声。可以降低带宽来降低噪声，因为倾斜应用通常需要低于1 kHz的带宽。</span></p>
<p><strong>表1ADXL345误差源估算值</strong></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">传感器参数</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 148.85pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">典型性能</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 120.5pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">条件/注释</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">典型</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: 宋体;">值</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">应用</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">误差（倾斜度）</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">噪声</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 148.85pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">X/Y轴290 μ</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;">/√Hz</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 120.5pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">6.25 Hz时的带宽</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 72.6pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.9 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.05°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 97.55pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">偏置漂移</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 148.85pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">Allan偏差</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">短期（例如：10天）</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">1 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.057°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">初始失调</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">35 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">无补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">35 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">2°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">有补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">误差</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 148.85pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">无补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 120.5pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">6.25 Hz带宽</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 72.6pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">36.9 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">2.1°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">误差</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">有补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 120.5pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">6.25 Hz带宽</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 72.6pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">1.9 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.1°</span></p>
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<p><span>表2列出了适用于</span><span>ADXL355</span><span>的同一标准。短期偏置值根据ADXL355数据手册中的Allan方差图估算。25℃时，通用ADXL345的补偿倾斜精度为0.1°，工业级ADXL355的补偿倾斜精度为0.005°。通过比较ADXL345和ADXL355可以看出，主要的误差促成因素引起的误差已显著降低，比如噪声引起的误差从0.05°降低到0.0045°，偏置漂移引起的误差从0.057°降低到0.00057°。这表明MEMS电容式加速度计在噪声、温度系数、失调以及偏置漂移等性能方面的巨大飞跃，在动态条件下能够提供更高水平的倾斜精度。</span></p>
<p><strong>表2ADXL355误差源估算值</strong></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">传感器参数</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.85pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">典型性能</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">条件/注释</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">典型</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: 宋体;">值</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">Application</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">Error Tilt °</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">应用</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">误差（倾斜度）</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">Noise</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">噪声</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">25 μ</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;">/√Hz</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">Band</span><span style="font-family: Arial;">width at 6.25 Hz</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">6.25 Hz时的带宽</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">78 μ</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.0045°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">Bias drift</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">偏置漂移</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">Allan deviation</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">Allan偏差</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">X/Y axis short-term (for example, 10 days)</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">X/Y轴短期（例如：10天）</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;"><10 μ</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.00057°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">初始失调</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td rowspan="2" style="width: 109.85pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">25 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">无补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">25 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">1.43°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">有补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">总误差</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">无补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">6.25 Hz带宽</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">25 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">1.43°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: 宋体;">总误差</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">有补偿</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">6.25 Hz带宽</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">88 m</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 109.9pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: justify;"><span style="font-family: Arial;">0.005°</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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</tbody>
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<p><span>选择更高等级的加速度计对于实现所需性能至关重要，特别是应用需要小于1°的倾斜精度时。应用精度取决于应用条件（温度大幅波动，振动）和传感器选择（消费级与工业级或战术级）。在这种情况下，ADXL345将需要大量的补偿和校准工作才能实现小于1°的倾斜精度，增加整个系统的工作量和成本。根据最终环境和温度范围内的振动大小，根本不可能实现上述精度。25℃至85℃范围内的温度系数失调漂移为1.375°，已经超过倾斜精度小于1°的要求。</span></p>
<p><img alt="干货 温度变化及振动条件下使用加速度计测量倾斜" data-entity-type="file" data-entity-uuid="fd45f147-9355-466c-8eb9-bf67072a596d" src="http://new.eetrend.com/files/2021-01/wen_zhang_/100061033-119549-1.jpg&…; /></p>
![http://new.eetrend.com/files/2021-01/wen_zhang_/100061033-119549-1.jpg&…](http://new.eetrend.com/files/2021-01/wen_zhang_/100061033-119549-1.jpg"){kind=link}
<p><span>25℃到85℃范围内ADXL355的温度系数失调漂移为：</span></p>
<p><img alt="干货 温度变化及振动条件下使用加速度计测量倾斜" data-entity-type="file" data-entity-uuid="2d8f38ff-f423-4264-9bca-aad5fcd2e065" src="http://new.eetrend.com/files/2021-01/wen_zhang_/100061033-119550-2.jpg&…; /></p>
![http://new.eetrend.com/files/2021-01/wen_zhang_/100061033-119550-2.jpg&…](http://new.eetrend.com/files/2021-01/wen_zhang_/100061033-119550-2.jpg"){kind=link}
<p><span>如表3所示，振动校正误差(VRE)是加速度计暴露于宽带振动时引入的失调误差。当加速度计暴露于振动环境时，相比温漂和噪声导致的0<span> </span></span><em>g</em><span>失调，VRE在倾斜测量中会导致明显误差。这是不再使用数据手册的主要原因之一，因为很容易掩盖其他主要规格。</span></p>
<p><strong>表3以倾斜度表示的误差</strong></p>
<table border="1" cellpadding="0" cellspacing="0" style="font-family: "Microsoft YaHei"; letter-spacing: normal; orphans: 2; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; margin-left: 0px; border: none; border-collapse: collapse;">
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">最大倾斜误差0<span> </span></span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: 宋体;">失调与温度之比(°/℃)</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">噪声密度(°/√HZ)</span><span style="font-family: Arial; font-weight: bold;"><span><o:p></o:p></span></span></p>
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<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">振动校正(°/</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;"><sup>2</sup></span><span style="font-family: Arial;">rms)</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
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<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">ADXL354</span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
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<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">0.0085</span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
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<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">0.0011</span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
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<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">0.023</span><span style="font-family: Arial;"><sup>1</sup></span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr>
<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">ADXL355</span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">0.0085</span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">0.0014</span><span style="font-family: Arial; color: rgb(143, 69, 255); font-weight: bold;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 137.35pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">0.023</span><span style="font-family: Arial;"><sup>1</sup></span></p>
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</tbody>
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<p><em>1</em><em>2.5 g rms振动导致的1 g方位失调的范围为±2 g</em></p>
<p><span>在具有较高振幅的环境中，必须使用较高</span><em>g</em><span>范围的加速度计才能最大限度减少削波导致的失调。表4列出了ADXL35x系列加速度计及其相应的</span><em>g</em><span>范围和带宽。</span></p>
<p><strong>表4ADXL354/ADXL355/ADXL356/ADXL357的测量范围</strong></p>
<table border="1" cellpadding="0" cellspacing="0" style="font-family: "Microsoft YaHei"; letter-spacing: normal; orphans: 2; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; margin-left: 0px; border: none; border-collapse: collapse;">
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<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">产品</span><span style="font-family: Arial; font-weight: bold;"><span><o:p></o:p></span></span></p>
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<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">测量范围(</span><span style="font-family: Arial; font-style: italic;">g</span><span style="font-family: Arial;">)</span><span style="font-family: Arial; font-weight: bold;"><span><o:p></o:p></span></span></p>
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<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: 宋体;">带宽(kHz)</span><span style="font-family: Arial; font-weight: bold;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr>
<td style="width: 183.1pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(0, 176, 240);">ADXL354B</span><span style="font-family: Arial; color: rgb(0, 176, 240);"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">±2, ±4</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">1</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr>
<td style="width: 183.1pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(0, 176, 240);">ADXL354C</span><span style="font-family: Arial; color: rgb(0, 176, 240);"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">±2, ±8</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">1</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr>
<td style="width: 183.1pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(0, 176, 240);">ADXL355B</span><span style="font-family: Arial; color: rgb(0, 176, 240);"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">±2, ±4, ±8</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">1.5</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
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<tr>
<td style="width: 183.1pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(0, 176, 240);">ADXL356B</span><span style="font-family: Arial; color: rgb(0, 176, 240);"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">±10, ±20</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">1.5</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr>
<td style="width: 183.1pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(0, 176, 240);">ADXL356C</span><span style="font-family: Arial; color: rgb(0, 176, 240);"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">±10, ±40</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">1.5</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr>
<td style="width: 183.1pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial; color: rgb(0, 176, 240);">ADXL357B</span><span style="font-family: Arial; color: rgb(0, 176, 240);"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">±10.24, ±20.48, ±40.96</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 183.15pt; background: transparent; border-width: 1pt; border-style: solid; border-color: windowtext; padding: 0pt 5.4pt;" valign="top">
<p class="MsoNormal" style="text-align: left;"><span style="font-family: Arial;">1</span><span style="font-family: Arial;"><span><o:p></o:p></span></span></p>
</td>
</tr>
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</table>
<p><span>选择适用于倾斜应用的ADXL35x系列加速度计将确保高稳定性和可重复性，可以耐受温度波动和宽带振动，并且相比较低成本的加速度计，所需的补偿和校准更少。该系列产品采用密封封装，可以确保最终产品出厂后重复性与稳定性始终符合规格参数。ADI公司的新一代加速度计可在所有环境下提供可重复的倾斜测量，它们在恶劣环境中无需进行大量校准即可实现最小倾斜误差。</span></p>
<p><strong>Chris Murphy</strong></p>
<p><span>Chris Murphy[christopher.murphy@analog.com]是欧洲中央应用中心的应用工程师，工作地点在爱尔兰都柏林。他于2012年加入ADI公司，为电机控制和工业自动化产品提供设计支持。他拥有电气工程研究硕士学位和计算机工程学士学位。</span></p>