htdzxiaoyao 发表于 2020-3-2 11:23

HB6296应用指南

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri">&nbsp;&nbsp;&nbsp;<span style="font-size:16.0000pt"><span style="font-family:宋体">&nbsp;HB6296<font face="宋体">应用指南</font></span></span></span></span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">一:电流检测电阻设法靠近</font>HB6296<font face="宋体">,检测电阻上电压信号很弱,为减少干扰,必须靠近</font><font face="Calibri">HB6296</font><font face="宋体">,应用图上对应的</font><font face="Calibri">R17.</font></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">二:</font>Regn<font face="宋体">上电容必须靠近</font><font face="Calibri">HB6296</font><font face="宋体">,越近越好。</font></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">三:这款</font>ic<font face="宋体">是经典的降压电路,电感计算公式可以参考。</font></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">四:电感计算公式:</font>L=<font face="宋体">(</font><font face="Calibri">Vin-Vbat</font><font face="宋体">)</font><font face="Calibri">*Ton/(Imax/D)</font><font face="宋体">。其中</font><font face="Calibri">D</font><font face="宋体">是占空比,</font><font face="Calibri">Ton=T*D</font><font face="宋体">。</font><font face="Calibri">L=(Vin-Vbat)*T</font><font face="宋体">。</font><font face="Calibri">T</font><font face="宋体">是开关周期,</font><font face="Calibri">Vbat</font><font face="宋体">取</font><font face="Calibri">3.7*n</font><font face="宋体">节。</font><font face="Calibri">HB6296</font><font face="宋体">的开关频率是变的,电压高是</font><font face="Calibri">350K</font><font face="宋体">,(</font><font face="Calibri">T=2.8us</font><font face="宋体">)。电压低是</font><font face="Calibri">1.8us</font><font face="宋体">。对</font><font face="Calibri">4</font><font face="宋体">节锂电,输入电压</font><font face="Calibri">25V</font><font face="宋体">,输出电流</font><font face="Calibri">5A</font><font face="宋体">。则</font><font face="Calibri">L=</font><font face="宋体">(</font><font face="Calibri">25-14.8</font><font face="宋体">)</font><font face="Calibri">*1.8us/5A=3.6uH</font><font face="宋体">。</font></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">五:散热。对于低压(小于</font>35V<font face="宋体">),我测试的结果</font><font face="Calibri">HB6296</font><font face="宋体">不需要加散热片,</font><font face="Calibri">P=(35V-5.4)*12ma=360mw,HB6296</font><font face="宋体">本身带散热片,外面可以不加。如果驱动</font><font face="Calibri">2</font><font face="宋体">个上管</font><font face="Calibri">mosfet</font><font face="宋体">,</font><font face="Calibri">Icc</font><font face="宋体">会上升到</font><font face="Calibri">20ma</font><font face="宋体">,这时</font><font face="Calibri">P=</font><font face="宋体">(</font><font face="Calibri">35-5.4</font><font face="宋体">)</font><font face="Calibri">*20ma=600mw</font><font face="宋体">,应该考虑加散热片。 </font><font face="Calibri">Mosfet</font><font face="宋体">的散热也要特别讲究。主要要考虑上管(</font><font face="Calibri">pwm</font><font face="宋体">管)。</font></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">六:</font>mosfet<font face="宋体">选择最好要用</font><font face="Calibri">Ciss</font><font face="宋体">小的,</font><font face="Calibri">tr</font><font face="宋体">,</font><font face="Calibri">tf</font><font face="宋体">比较短的,</font><font face="Calibri">mosfet</font><font face="宋体">。这样</font><font face="Calibri">mosfet</font><font face="宋体">发热少,</font><font face="Calibri">HB6296</font><font face="宋体">发热也少。但是也不能太少,太少电感波形太陡,</font><font face="Calibri">emc</font><font face="宋体">和</font><font face="Calibri">emi</font><font face="宋体">过不去,也干扰</font><font face="Calibri">HB6296</font><font face="宋体">。</font></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:10.5pt"><span style="font-family:Calibri"><span style="font-size:15.0000pt"><span style="font-family:宋体"><font face="宋体">七:为了</font>emc<font face="宋体">和</font><font face="Calibri">emi</font><font face="宋体">的考虑,主电流回路要越短越好,交流回路也要越短越好,特别是</font><font face="Calibri">lx</font><font face="宋体">这个</font><font face="Calibri">net</font><font face="宋体">上,交流通路可以用</font><font face="Calibri">4.7uf</font><font face="宋体">的瓷片电容放置相关的地方,比较有效的减少交流通路的长度。</font></span></span></span></span></p>

<p><br />
<br />
<b><font color="#5E7384">此内容由EEWORLD论坛网友<font size="3">htdzxiaoyao</font>原创,如需转载或用于商业用途需征得作者同意并注明出处</font></b></p>

高进 发表于 2020-3-2 13:55

<p>写的不错,楼主加油</p>
页: [1]
查看完整版本: HB6296应用指南