<p><span>我们一直在通过减少元器件的数量和节约印刷</span><span>电路板</span><span>的</span><span>尺寸</span><span>来追求系统设计的最优化。</span></p>
<p><span>增添</span><span>小型、低</span><span>成本</span><span>的微控制器（MCU）以实现简单的</span><span>辅助</span><span>处理功能，可</span><span>以对</span><span>许多电路</span><span>的</span><span>设计</span><span>产生助益</span><span>。</span><span>该通用</span><span>MCU并非系统中主要的处理器，但它可处理一些</span><span>必不可少</span><span>的系统级功能，如LED控制或输入/输出扩展。本文中，我将说明如何在系统中集成多功能</span><span>通用</span><span>处理MCU来</span><span>缩减</span><span>物料清单（BOM）成本</span><span>，</span><span>节省电路板空间，并最大程度地简化设计。</span></p>
<p><span>例如，假如您要创建一个具有以下功能的新设计：</span></p>
<ul>
<li><span>LED控制</span></li>
<li><span>I/O扩展</span></li>
<li><span>带电可擦可编程存储</span><span>器</span><span>（EEPROM）</span></li>
<li><span>外部</span><span>看门狗时钟</span></li>
</ul>
<p><span>您</span><span>可使用分立</span><span>元器件</span><span>来实现所有功能。也可</span><span>以</span><span>考虑在</span><span>通用</span><span>MCU上执行软件</span><span>实现同样的</span><span>功能，以</span><span>降低复</span><span>杂性并</span><span>减</span><span>小电路板</span><span>的</span><span>尺寸，如图1所示。</span></p>
<p><img alt="图1：在单个通用MSP430 MCU上实现软件中多个分立元器件的功能" data-entity-type="file" data-entity-uuid="cf0dc3f2-046a-44cb-8028-04db44d918df" src="http://new.eetrend.com/files/2020-12/wen_zhang_/100060110-117145-1.jpg&…; /></p>
![http://new.eetrend.com/files/2020-12/wen_zhang_/100060110-117145-1.jpg&…](http://new.eetrend.com/files/2020-12/wen_zhang_/100060110-117145-1.jpg"){kind=link}
<p><strong>图1：在单个</strong><strong>通用</strong><strong>MSP430 MCU上实现软件中多个分立</strong><strong>元器件</strong><strong>的功能</strong></p>
<p><span>另一个</span><span>值得考虑的</span><span>设计方面的挑战</span><span>——</span><span>也</span><span>许</span><span>是一个最为重要</span><span>的挑战——</span><span>就是符合您的设计预算要求。</span></p>
<p><span>例如，</span><span>如果采用分立元器件方法实现这些功能</span><span>，您可预估大致的</span><span>物料清单</span><span>成本</span><span>。举例来说，</span><span>具备包括LED控制、五通道I/O扩展器、串行</span><span>EEPROM</span><span>和外部看门狗时钟等功能的</span><span>多个分立</span><span>元器件方案</span><span>总计将花费约0.97美元。</span><span>与此相比，8</span><span>-</span><span>KB MSP430 MCU的当前网络价格不到0.25美元。</span><span>这可</span><span>大大</span><span>节</span><span>约了</span><span>成本！</span></p>
<p><span>如果您</span><span>需要</span><span>更</span><span>大</span><span>或更</span><span>小</span><span>内存的</span><span>通用</span><span>MCU，可在MSP430 MCU产品系列中</span><span>发现</span><span>不同内存和</span><span>配置</span><span>的</span><span>丰富的</span><span>选择。</span><span>具体信息请登录T</span><span>I</span><span>.</span><span>com.cn</span><span>查询。</span></p>
<table border="1" cellpadding="0" cellspacing="0" style="font-family: "Microsoft YaHei"; letter-spacing: normal; orphans: 2; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-style: initial; text-decoration-color: initial; border: none; border-collapse: collapse; width: 222px;" width="32%">
<tbody>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt 0pt 5pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian; font-weight: bold;">内存</span><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian; font-weight: bold;">产品</span><span style="font-size: 11pt; font-family: DengXian; font-weight: bold;">型号</span><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian;">0.5 kB<span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><a href="https://www.ti.com.cn/product/cn/MSP430FR2000" title="Product Folder"><span style="font-size: 11pt; font-family: DengXian; color: windowtext; text-decoration: underline;">MSP430FR2000</span></a><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian;">1 kB<span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><a href="https://www.ti.com.cn/product/cn/MSP430FR2100" title="Product Folder"><span style="font-size: 11pt; font-family: DengXian; color: windowtext; text-decoration: underline;">MSP430FR2100</span></a><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian;">2 kB<span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><a href="https://www.ti.com.cn/product/cn/MSP430FR2110" title="Product Folder"><span style="font-size: 11pt; font-family: DengXian; color: windowtext; text-decoration: underline;">MSP430FR2110</span></a><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian;">4 kB<span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><a href="https://www.ti.com.cn/product/cn/MSP430FR2111" title="Product Folder"><span style="font-size: 11pt; font-family: DengXian; color: windowtext; text-decoration: underline;">MSP430FR2111</span></a><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian;">8 kB<span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><a href="https://www.ti.com.cn/product/cn/MSP430FR2422" title="Product Folder"><span style="font-size: 11pt; font-family: DengXian; color: windowtext; text-decoration: underline;">MSP430FR2422</span></a><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
<tr style="height: 28.35pt;">
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><span style="font-size: 11pt; font-family: DengXian;">16 kB<span><o:p></o:p></span></span></p>
</td>
<td style="width: 85.05pt; border-width: 1pt; border-style: outset outset solid; border-color: windowtext windowtext rgb(153, 153, 153); padding: 0pt 5.4pt;" valign="middle">
<p class="MsoNormal" style="margin-bottom: 12pt; text-align: center; line-height: normal;"><a href="https://www.ti.com.cn/product/cn/MSP430FR2433" title="Product Folder"><span style="font-size: 11pt; font-family: DengXian; color: windowtext; text-decoration: underline;">MSP430FR2433</span></a><span style="font-size: 11pt; font-family: DengXian;"><span><o:p></o:p></span></span></p>
</td>
</tr>
</tbody>
</table>
<p><strong>表1：TI.com</strong><strong>.</strong><strong>cn</strong><strong>上的通用</strong><strong>MSP430 MCU</strong><strong>主打产品列表</strong></p>
<p><span>采用</span><span>集成</span><span>度好的通用化</span><span>MCU</span><span>的设计方案</span><span>不仅可减小电路板尺寸、减少</span><span>元器件</span><span>数量，还可降低</span><span>整体</span><span>物料成本。</span><span>您</span><span>可在网络研讨会</span><span>“</span><a href="https://training.ti.com/msp430-mcu-webinar-simpler-system-monitoring"><…：</span></a><a href="https://training.ti.com/msp430-mcu-webinar-simpler-system-monitoring"><… MCU</span></a><span>。”</span><span>中</span><span>了解</span><span>更多关于</span><span>这些设计</span><span>的信息</span><span>。</span></p>
<p><strong>示例</strong><strong>应用程序：在</strong><strong>通用</strong><strong>MCU上实现ADC唤醒和传输功能</strong></p>
<p><span>让我们来看一个示例，说明如何在设计中真正实现</span><span>辅助</span><span>处理功能。</span></p>
<p><span>一种常见的</span><span>设计</span><span>是</span><span>在</span><span>电路板上</span><span>配置一块</span><span>模数转换器（ADC），</span><span>并同</span><span>其他</span><span>诸如</span><span>电池监</span><span>控</span><span>器或温度传感器</span><span>等</span><span>设备连接。在此示例中，ADC必须定期</span><span>对</span><span>来自传感器的模拟信号</span><span>进行采样</span><span>，并将此数据发送回MCU，而MCU将根据这些信号</span><span>的情况</span><span>进行操作。</span></p>
<p><span>如果MCU使用定时器来触发ADC读取，甚至连续接收ADC</span><span>返回的</span><span>值，则</span><span>会增加系统功耗</span><span>。一种解决方案是将ADC集成到MCU中，并独立于中央处理器（CPU）进行操作。如此，MCU的其余部分可以进入</span><span>休</span><span>眠状态，</span><span>仅在A</span><span>DC读取的值超过某个阈值时才</span><span>被</span><span>予以唤醒。此时，ADC将</span><span>发出中断信号</span><span>并唤醒MCU。</span></p>
<p><span>我们在有关</span><span>辅助</span><span>处理功能</span><span>“</span><span>使用MSP430 MCU通过阈值进行ADC唤醒并传输数据。</span><a href="https://training.ti.com/msp-mcu-training-adc-wake-and-transmit-english"…;”</span></a><span>的培训视频中，对该应用加以说明。</span><span>在</span><span>本视频中，我们展示了一个图形用户界面（GUI），演示ADC值的读取以及</span><span>中断信号</span><span>的</span><span>传输</span><span>，以便在达到阈值后唤醒CPU。</span></p>
<p><strong>结论</strong></p>
<p><span>使用另一个</span><span>小型</span><span>MCU执行</span><span>辅助</span><span>处理功能是简化设计的好方法。</span><span>通用型MSP430MCU具备超低功耗和模拟外设独立监控的特点很适合这类应用，</span><span>另外，借助我们的软件和</span><span>图形化界面</span><span>，您可在数分钟内对MSP430设备进行编程，以</span><span>实现</span><span>各类功能。</span></p>
<p><strong>其他资源</strong></p>
<p><span>1.</span><span>在应用指南</span><span>《</span><a href="https://www.ti.com/lit/pdf/slaa963"><span>使用MSP430 MCU通过阈值进行ADC唤醒并传输数据</span></a><span>》</span><span>中了解有关ADC唤醒和传输功能的更多信息。</span></p>
<p><span>2.</span><span>在</span><a href="https://www.ti.com.cn/tool/cn/MSP-EXP430FR2433"><span>MSP430FR2433 LaunchPad™开发套件</span></a><span>上查看ADC唤醒和传输软件示例。</span></p>
<p><span>3.</span><span>观看我们的</span><span>培训视频“使用通用MCU通过阈值进行ADC唤醒并传输数据”</span></p>
<p><span>4.</span><span>下载并测试此示例</span><span>：</span><a href="https://dev.ti.com/gallery/view/1579610/ADC_LPM_FR2433_GUI/"><span>ADC唤…;