将电源(24)脚和④脚排插分别对应插到主板上的插座,通电试机时,电源指示灯时亮时灭,电源风扇和CPU风扇都时转时停,蜂鸣器无通电自检声。测电源各输出脚与地间电压,除紫线与地间电压为稳定的5V,绿线与地间的电压为稳定的,其余各脚与地间的电压都在不停地跳变,说明主板中存在严重的短路故障,拔掉光驱和硬盘的数据线和电源线,通电故障不变。取下CPU和内存条通电,电源风扇时转时停,CPU风扇不转。插入内存条,试短路绿黑线,电源风扇高速旋转,CPU风扇不转,试摸主板各芯片,发现SWSCSOH5514E-NSE0810-A404158S1332860烫手,立即断电。检测数据说明,同一个厂家的不同主板,虽然使用电压相同的电源供电,但其供电脚与地间的正向电阻却相差很多,且供电脚与地间的正反向电阻有时相同,有时相差很大。用测主板各供电脚与地间的正反向电阻查出该主板的短路故障难度很大,只能用测大功率管和各晶体管PN结的正反向电阻来寻求突破。用DT830B数字万用表二极管挡测完主板上的所有晶体管,发现Q55(N790A-EF814)的②脚与③脚间正反向电阻都为4Ω,Q54(N790A-EF814)的②脚与③脚间正反向电阻都为3Ω,Q52(748T40N03G)的②脚与③脚间正向电阻为llΩ,反向电阻为12Ω。 外壳(亥姆霍兹共振声腔)频率、磁环的磁强漆包线的线径有直接关系。虹口区施耐德AD16系列蜂鸣器哪家强
振荡回路30会根据第二开关管q2和第三开关管q3的状态变化而改变振荡回路,振荡回路改变时,电容c1两端的压差由2*vcc变为4*vcc,增加了蜂鸣器两端的压差变化。本发明的有益效果:1.上述蜂鸣器驱动电路由电感l1、第二点l2和电容c1组成的振荡回路驱动蜂鸣器,同时由第三电感l3和第二开关管q2、第三开关q3组成的振荡控制电路对所述振荡回路进行稳定的闭环控制,使振荡回路工作时的振荡波形稳定,在蜂鸣器两端产生标准正弦波,驱动蜂鸣器发声,无需mcu输出pwm来驱动蜂鸣器,从而减少mcu的io口占用,节省了主控mcu的资源;此外,标准正弦波作用于蜂鸣器两端,蜂鸣器发出的声音比由pwm方波驱动的蜂鸣器发出的声音效果更好,没有杂音,从而改善蜂鸣器音质。2.第二开关管q2、第三开关q3会同步振荡频率改变振荡电路,从而引起蜂鸣器两端更大的变化,增加了蜂鸣器两端的压差,进而增强了蜂鸣器的音量。3.上述蜂鸣器驱动电路包括电源控制电路10,电源控制电路10根据mcu产生简单的高低电平控制所述蜂鸣器驱动电路是否对gnd形成回路从而控制蜂鸣器的工作状态,确保了整个电路的可控性和有效性,整个控制过程可靠且迅速。长宁区制造AD16系列蜂鸣器推荐厂家开孔尺寸:φ16mm; 通过声音来指示不同工作状态。
电路图箭头朝里:PNP单极管;箭头朝外:NPN的单极管小圆圈为插针。用一根杜邦线将插针与单片机引脚相连,单片机引脚输出低电平,单极管导通,e、c连通,形成回路,有源蜂鸣器发声;无源蜂鸣器需要(与蜂鸣器种类有关,实际使用时可测试)的音频信号,即产生一个不断的高低电平变化,高低电平变化频率为3、单片机I/O口驱动能力非常微弱,不可以通过单片机I/O口直接驱动蜂鸣器,必须通过外接驱动电路,使R39电阻,单极管和R19电阻构成电流的放大电路从而可以驱动蜂鸣器,而不是依靠单片机管脚驱动蜂鸣器4、占空比:高电平时间方波:高电平、低电平时间相同~:取反符号,将管脚输出电平状态取反含有上拉电阻,默认输出高电平。高低电平各延时一段时间。
ex502380-1300Molex52465-3071Molex35184-1200Molex38770-0105Molex43030-0006Molex44428-0602Molex502380-1400Molex52465-4071Molex35184-1400Molex38770-0106Molex43030-0006Molex44428-0801Molex502380-1500Molex52480-4810Molex35189-0110Molex38770-0107Molex43030-0007袋装(43030-0001卷)Molex44428-0802Molex502381-0000Molex35189-0200Molex38770-0108Molex43030-0008Molex44428-0803Molex502381-0000Molex52484-0310Molex35189-0201Molex38770-0109Molex43030-0009单粒=卷带43030-0003Molex44428-1001Molex502382-0270Molex35189-0210Molex38770-0110Molex43030-0010单粒=43030-0004Molex44428-1002Molex502382-0370Molex52484-0510Molex35189-0261Molex38770-0111Molex43030-0011Molex44428-1201Molex502382-0470Molex52484-0510Molex35189-0274Molex38770-0112Molex43030-0012Molex44428-1202Molex502382-0570Molex52484-0710Molex35189-0281Molex38770-0113Molex43030-0053Molex44428-1401Molex502382-0670Molex52484-0810Molex35189-0290Molex38770-0114Molex43031-0001Molex44428-1402Molex502382-0770Molex52559-0652Molex35189-0360Molex38770-0115Molex430。电磁无源蜂鸣属于感性负载器件,理想输入是正向方波通常记作:VO-P。
5559-02P)Molex43045-1422Molex45481-0270Molex50-36-1678Molex52808-1370Molex35749-0810Molex39-01-2025(5557-02R-210)Molex43045-1424Molex45481-0283Molex50-36-1687Molex52808-1371Molex35749-0910Molex39-01-2026Molex43045-1425Molex45483-0130Molex50-36-1688Molex52808-1470Molex35749-1460Molex39-01-2026Molex43045-1426Molex45483-0087Molex50-36-1713Molex52808-1471Molex35750-0810Molex39-01-2026Molex43045-1600Molex45483-0078Molex50-36-1716Molex52808-1670Molex35750-0910Molex39-01-20405557-04RMolex43045-1601Molex45483-0418Molex50-36-1734Molex52808-1870Molex35750-1010Molex39-01-20405557-04RMolex43045-1602Molex45485-0093Molex50-36-1869Molex52808-2071Molex35750-1210Molex39-01-20405557-04RMolex43045-1606Molex45485-0224Molex50-36-1871Molex52808-2271Molex35750-1910Molex39-01-20405557-04RMolex43045-1609Molex45485-0223Molex50-36-2277Molex52808-2370Molex35750-4810Molex39-01-20415559-04PMolex43045-1610Molex45485-0128Molex50-36-2301Molex52808-3070Molex35760-7200Molex39-01-20415559-04PMolex43045-1612Molex45504-0。在一些特例中,可以和LED复用一个控制口 有源蜂鸣器的优点是:程序控制方便。虹口区施耐德AD16系列蜂鸣器哪家强
压电蜂鸣片是将高压极压化后的压电陶瓷片黏贴于振动金属片上。虹口区施耐德AD16系列蜂鸣器哪家强
0211Molex35151-0410Molex38740-4608Molex42878-8408Molex39532-1005Molex501951-2410Molex52266-0311Molex35151-0410Molex38740-5410Molex42878-8410Molex39532-1006Molex501951-3000Molex52266-0417Molex35151-0410Molex38740-6102Molex42878-8456Molex39532-1008Molex501951-4000Molex52271-0469Molex35151-0414Molex38740-6103Molex42878-8458Molex39532-1009Molex501951-4010Molex52271-0479Molex35151-0419Molex38740-6104Molex42878-8506Molex39532-1010Molex501951-4500Molex52271-0569Molex35151-0610Molex38740-6308Molex43009-0084Molex39532-1012Molex501951-4510Molex52271-0579Molex35151-0610Molex38740-6309Molex43020-0200Molex39-53-2104Molex501951-5000Molex52271-0679Molex35151-0619Molex38740-6314Molex43020-0201Molex39-53-2105Molex501951-5010Molex52271-0769Molex35153-0500Molex38740-7303Molex43020-0400Molex39-53-2114Molex501951-6000Molex52271-0779Molex35155-0200Molex38740-7304Molex43020-0401Molex39-53-2115Molex501951-6010Molex52271-0869Molex35155-0200Molex38741-3304Molex43020-0600。虹口区施耐德AD16系列蜂鸣器哪家强
ex38779-0409Molex43045-0222Molex44472-1254Molex502430-8010Molex52584-1079Molex35313-0360Molex38779-0462Molex43045-0224Molex44472-1255Molex502438-0000Molex52584-1279Molex35313-0360Molex38780-0102Molex43045-0400Molex44472-1653Molex502438-0100单粒=502438-0000卷带Molex52584-1479Molex35313-0460Molex38780...