topic Re: 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 in Motor Control and Smart Energy https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491614#M12 <HTML><HEAD></HEAD><BODY><P>Hi, LongJie,</P><P>关于PWM分辨率，对于KV31, PWM驱动时钟是BUS CLOCK, 只有40MHz, 周期是0.025us. 如果PWM频率是200Khz, 则分频数是200, 分辨率只有不到8 bits.</P><P>我推建你用KV5x 或 KV4x 系列， 其PWM 模块用eFlexPWM, 它的特点是可以用32倍小数分频。 KV4 PWM可以达到260ps的分辨率。</P><P>The Kinetis KV4x MCU family is a member of the Kinetis V</P><P>series and provides a high-performance solution for 3-phase</P><P>BLDC, PMSM and ACIM motor control as well as Digital Power</P><P>Conversion. Built upon the ARM® Cortex®-M4 core operating at</P><P>150 MHz with DSP and floating point unit, features include; dual</P><P>12-bit analog-to-digital converters with 240ns conversion time,</P><P>up to 30 PWM channels for support of multi-motor systems,</P><P>eFlexPWM module with 260ps resolution for digital power</P><P>conversion applications, programmable delay block, memory</P><P>protection unit, dual FlexCAN modules and 64 to 256 KB of flash</P><P>memory. KV4x MCUs are offered in 48LQFP, 64LQFP, and</P><P>100LQFP packages. All Kinetis V series MCUs are supported by</P><P>a comprehensive enablement suite from Freescale and thirdparty</P><P>resources including reference designs, software libraries</P><P>and motor configuration tools.</P><P>这是KV系列的website:</P><P><A href="http://www.nxp.com/products/microcontrollers-and-processors/arm-processors/kinetis-cortex-m-mcus/v-series:KINETIS_V_SERIES" title="http://www.nxp.com/products/microcontrollers-and-processors/arm-processors/kinetis-cortex-m-mcus/v-series:KINETIS_V_SERIES">ARM Cortex-M0+/M4/M7 Cores|Kinetis V MCUs|NXP</A> </P><P>BR</P><P>XiangJun Rong</P></BODY></HTML> Tue, 01 Mar 2016 04:13:18 GMT xiangjun_rong 2016-03-01T04:13:18Z 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491611#M9 <HTML><HEAD></HEAD><BODY><P>请问：</P><P>目前计划设计一个数字闭环的DCDC，只用作降压。</P><P>1，输入6-24V</P><P>2、输出0-20V,0-100A，因为只用作降压，所以输出电压只能低于输入电压</P><P>3，电压和电流输出精度要求0.3%FS</P><P>4，瞬态响应不做要求</P><P>请问这样的性能要求使用<A _jive_internal="true" href="https://community.nxp.com/external-link.jspa?url=http%3A%2F%2Fcn.element14.com%2Ffreescale-semiconductor%2Fmkv30f64vlh10%2Fmcu-32bit-cortex-m4-100mhz-lqfp%2Fdp%2F2450723" rel="nofollow" target="_blank">MKV30F64VLH10</A>这个芯片可以吗。或者能不能推荐一个合适的芯片，只要ARM核心的。</P><P>有没有一个可以参考的设计或者资料。</P><P>谢谢！</P></BODY></HTML> Mon, 29 Feb 2016 02:50:42 GMT https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491611#M9 lilongjie 2016-02-29T02:50:42Z Re: 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491612#M10 <HTML><HEAD></HEAD><BODY><P>Hi, LongJie,</P><P>当你选择芯片时， 你首先考虑DC/DC变换器的拓补结构， 要求的PWM波形, 是否要电流环， PWM频率， 计算量，ADC 精度..., 我们需要详细的信息。 不过，我认为KV系列可以满足你的要求。</P><P>我们有DC/DC converter, 但是是基于DSC 的。</P><P>请参考：</P><P><A href="http://www.nxp.com/products/microcontrollers-and-processors/more-processors/dsp-dsc/dscs/mc56f84xxx/digital-signal-controllers:MC56F84xxx?fpsp=1&amp;tab=Documentation_Tab" title="http://www.nxp.com/products/microcontrollers-and-processors/more-processors/dsp-dsc/dscs/mc56f84xxx/digital-signal-controllers:MC56F84xxx?fpsp=1&amp;tab=Documentation_Tab">MC56F84xxx|Digital Signal Controllers|NXP</A> </P><P>BR</P><P>Xianjun rong</P></BODY></HTML> Mon, 29 Feb 2016 08:35:32 GMT https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491612#M10 xiangjun_rong 2016-02-29T08:35:32Z Re: 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491613#M11 <HTML><HEAD></HEAD><BODY><P>你好！</P><P></P><P></P><P>因为电路是降压的，所以计划使用BUCK拓扑。</P><P>至于反馈环路，我计划是使用纯数字反馈：ADC采集输出电压和电流，然后修改PWM的占空比。</P><P>之所以选中KV3是因为他的高速16位ADC。</P><P></P><P></P><P>我计算了一下关于系统性能的需求</P><P>1、输出精度需要0.3%FS，因此实际精度应该是需要达到0.1%左右才能保证使用过程中能保持在0.3%FS以内。</P><P>如果是这样，就要求ADC和PWM的分辨率达到输出精度的10倍也就是10000。</P><P>KV3的ADC是16位的有效值大约是13-14位正好符合需求。</P><P>然后看PWM分辨率，系统计划使用威世的大功率MOS，开关频率200K，这时候就需要PWM的步进值是1S/(200K*10000) = 500ps。但是KV3的最小步进只有0.025ns。这点达不到系统的要求，也正是我为难的地方。</P><P></P><P></P><P>2、反馈环的速度：因为我的应用比较特殊，是使用一个直流非稳压的输入对蓄电池组充电。输入和输出相对比较稳定，系统不需要太过于关心负载调整率之类的参数。KV3的双ADC在16位差分的情况下能达到300K左右，开关频率是200K，这点应该是没有问题的。</P><P></P><P></P><P>总结：也就是说现在主要就是PWM的分辨率问题需要解决：1、需要输出频率必须到200K。2、需要分辨率必须到10000.</P><P>这些问题有办法解决吗？做这样一个DCDC还需要考虑什么问题？</P><P></P><P></P><P>谢谢！</P></BODY></HTML> Tue, 01 Mar 2016 01:24:44 GMT https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491613#M11 lilongjie 2016-03-01T01:24:44Z Re: 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491614#M12 <HTML><HEAD></HEAD><BODY><P>Hi, LongJie,</P><P>关于PWM分辨率，对于KV31, PWM驱动时钟是BUS CLOCK, 只有40MHz, 周期是0.025us. 如果PWM频率是200Khz, 则分频数是200, 分辨率只有不到8 bits.</P><P>我推建你用KV5x 或 KV4x 系列， 其PWM 模块用eFlexPWM, 它的特点是可以用32倍小数分频。 KV4 PWM可以达到260ps的分辨率。</P><P>The Kinetis KV4x MCU family is a member of the Kinetis V</P><P>series and provides a high-performance solution for 3-phase</P><P>BLDC, PMSM and ACIM motor control as well as Digital Power</P><P>Conversion. Built upon the ARM® Cortex®-M4 core operating at</P><P>150 MHz with DSP and floating point unit, features include; dual</P><P>12-bit analog-to-digital converters with 240ns conversion time,</P><P>up to 30 PWM channels for support of multi-motor systems,</P><P>eFlexPWM module with 260ps resolution for digital power</P><P>conversion applications, programmable delay block, memory</P><P>protection unit, dual FlexCAN modules and 64 to 256 KB of flash</P><P>memory. KV4x MCUs are offered in 48LQFP, 64LQFP, and</P><P>100LQFP packages. All Kinetis V series MCUs are supported by</P><P>a comprehensive enablement suite from Freescale and thirdparty</P><P>resources including reference designs, software libraries</P><P>and motor configuration tools.</P><P>这是KV系列的website:</P><P><A href="http://www.nxp.com/products/microcontrollers-and-processors/arm-processors/kinetis-cortex-m-mcus/v-series:KINETIS_V_SERIES" title="http://www.nxp.com/products/microcontrollers-and-processors/arm-processors/kinetis-cortex-m-mcus/v-series:KINETIS_V_SERIES">ARM Cortex-M0+/M4/M7 Cores|Kinetis V MCUs|NXP</A> </P><P>BR</P><P>XiangJun Rong</P></BODY></HTML> Tue, 01 Mar 2016 04:13:18 GMT https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491614#M12 xiangjun_rong 2016-03-01T04:13:18Z Re: 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491615#M13 <HTML><HEAD></HEAD><BODY><P>你好！</P><P>我看到了这个芯片，有两个问题：</P><P>1、这个芯片的ADC虽然速度比较快，但是他的分辨率只有12位，按照我的估计需要至少13位以上的分辨率才能实现<SPAN style="color: #51626f; font-family: arial, helvetica, 'helvetica neue', verdana, sans-serif;">0.1%的精度，这个12位的可以实现吗？</SPAN></P><P><SPAN style="color: #51626f; font-family: arial, helvetica, 'helvetica neue', verdana, sans-serif;">2、这个芯片的购买渠道是个问题，我们一般在e络盟或者贸泽购买，但是这个都是几乎没货，有货的都是比较贵的型号，最便宜的型号没有。</SPAN></P></BODY></HTML> Wed, 02 Mar 2016 03:53:32 GMT https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491615#M13 lilongjie 2016-03-02T03:53:32Z Re: 设计一个DCDC输入24V输出0-20V,0-100A的电源，使用KV3 https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491616#M14 <HTML><HEAD></HEAD><BODY><P>Hi,LongJie,</P><P>12 bits ADC的分辨率是1/4096。 如果你需要更高的PWM分辨率和ADC分辨率， 建议用最新的KV5x系列。 KV5x具有260ps的PWM分辨率, SAR ADC分辨率可以达到16 bits.</P><P></P><P>NXP芯片可以通过代理商购买， 也可以在NXP网站上直接购买。 但KV5X还没有批量生产。</P><P></P><P>BR</P><P>XiangJun 容</P></BODY></HTML> Thu, 03 Mar 2016 03:26:44 GMT https://community.nxp.com/t5/Motor-Control-and-Smart-Energy/%E8%AE%BE%E8%AE%A1%E4%B8%80%E4%B8%AADCDC%E8%BE%93%E5%85%A524V%E8%BE%93%E5%87%BA0-20V-0-100A%E7%9A%84%E7%94%B5%E6%BA%90-%E4%BD%BF%E7%94%A8KV3/m-p/491616#M14 xiangjun_rong 2016-03-03T03:26:44Z