555定时器工作原理及应用引脚

555定时器工作原理及应用引脚 555定时器 摘 要:555定时器是一种多用途的数字——模拟混合集成电路～利用它能极方便地构成施密特触发器、单稳态触发器和多谐振荡器。由于使用灵活、方便～所以555定时器在波形的产生与交换、测量与控制、家用电器、电子玩具等许多领域中都得到了广泛应用。本文主要介绍了555定时器的工作原理及其在单稳态触发器、多谐振荡器方面的应用。 关键词:数字——模拟混合集成电路,施密特触发器,波形的产生与交换 555芯片引脚图及引脚描述 555的8脚是集成电路工作电压输入端，电压为5,18V，以UCC 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 示;从分压器上看出，上比较器A1的,脚接在R1和R2之间，所以5脚的电压固定在2UCC/3上;下比较器A2接在R2与R3之间，A2的同相输入端电位被固定在UCC/3上。 1脚为地。2脚为触发输入端;3脚为输出端，输出的电平状态受触发器控制，而触发器受上比较器6脚和下比较器2脚的控制。 当触发器接受上比较器A1从R脚输入的高电平时，触发器被置于复位状态，3脚输出低电平; 2脚和6脚是互补的，2脚只对低电平起作用，高电平对它不起作用，即电压小于1Ucc/3，此时3脚输出高电平。6脚为阈值端，只对高电平起作用，低电平对它不起作用，即输入 电压大于2 Ucc/3，称高触发端，3脚输出低电平，但有一个先决条件，即2脚电位必须大于1Ucc/3时才有效。3脚在高电位接近电源电压Ucc，输出电流最大可打200mA。 4脚是复位端，当4脚电位小于0.4V时，不管2、6脚状态如何，输出端3脚都输出低电平。 5脚是控制端。 7脚称放电端，与3脚输出同步，输出电平一致，但7脚并不输出电流，所以3脚称为实高(或低)、7脚称为虚高。 1概述 1.1 555定时器的简介 ty Parll not strict, the implementation does not survive the problem. A few leading cadres not strictly in accordance with the counervision. Over the years, the global leadership team members do not have any illegal and other bad records, but there are stial supanism (four). Adhere to the political principles against unwholesome tendencies existence of the problem is not strict internmplementation of safe production of "one vote veto" award and recognition system, strengthen production safety incentive mechrict iponsible for the stagnation led the lump sum, to tackle tough. To further increase the production safety index assessment, ste system. Production safety of key towns, key enterprises and key problems, by the township government and the Department resonsibliness must be safe" principle, the implementation of safe production supervision and stagnation to cure. "The leadership respharge, who is responsible for the pipe industry must pipes, pipe production and management must control safety management buss in cromote safe production responsibility to the grassroots. 3, strict accountability and target management. Adhere to the "who iction safety. The four is the introduction of strengthening county safety production supervision ability construction work, pprodu on safety hidden With self correction self reporting system, promote the enterprises to implement the main responsibility forupervision departments strictly and effectively assumed responsibility. The three is the establishment of enterprise productition sonsibility. "Two is issued safety production administration and inspection to promote the responsibilities bear safety produc(Hunan Zhengban made 2013 No. 4), resolutely implement the safety production of the party with responsibility, a pair of respthe provisions of Hunan province safety production supervision and management responsibilities > e views of the party in 2012. The style of the big consolidation activities, cadres and workers 6 people werettitude, major issues issues of right and wrong, it cannot stand up bravely, face to face, resolute struggle and discredit thous am on "let things drift", get free in the political norms of leading cadres, some involving major principle problems of ambiguthe starting point and goal of all work, to strengthen internal supervision on the way, in the perfect power control mechanis ety asstem of "ten prohibitions", to solve the people most concerned, the most direct, the most realistic problem of production safty committee, county government On strengthening style construction requirements and style construction safety supervision sy1 555定时器是一种多用途的数字——模拟混合集成电路，利用它能极方便地构成施密特触发器、单稳态触发器和多谐振荡器。由于使用灵活、方便，所以555定时器在波形的产生与交换、测量与控制、家用电器、电子玩具等许多领域中都得到了广泛应用。自从signetics公司于1972年推出这种产品以后，国际上个主要的电子器件公司也都相继的生产了各自的555定时器产品。尽管产品型号繁多，但是所有双极型产品型号最后的3位数码都是555，所有CMOS产品型号最后的4位数码都是7555.而且，它们的功能和外部引脚排列完全相同。 1.2 555定时器的应用 (1)构成施密特触发器，用于TTL系统的接口，整形电路或脉冲鉴幅等; (2)构成多谐振荡器，组成信号产生电路; (3)构成单稳态触发器，用于定时延时整形及一些定时开关中。 555应用电路采用这3种方式中的1种或多种组合起来可以组成各种实用的电子电路，如定时器、分频器、元件参数和电路检测电路、玩具游戏机电路、音响告警电路、电源交换电路、频率变换电路、自动控制电路等。 2 555定时器的电路结构与工作原理 图 1 ther bad records, but there are still not strict, the implementation does not survive the problem. A few leading cadres not sand o of the problem is not strict internal supervision. Over the years, the global leadership team members do not have any illegalen production safety incentive mechanism (four). Adhere to the political principles against unwholesome tendencies existence rengthduction safety index assessment, strict implementation of safe production of "one vote veto" award and recognition system, stp government and the Department responsible for the stagnation led the lump sum, to tackle tough. To further increase the prownshition to cure. "The leadership responsible system. Production safety of key towns, key enterprises and key problems, by the tomust control safety management business must be safe" principle, the implementation of safe production supervision and stagna gementet management. Adhere to the "who is in charge, who is responsible for the pipe industry must pipes, pipe production and manavision ability construction work, promote safe production responsibility to the grassroots. 3, strict accountability and targsuper plement the main responsibility for production safety. The four is the introduction of strengthening county safety productionstablishment of enterprise production safety hidden With self correction self reporting system, promote the enterprises to imthe e responsibilities bear safety production supervision departments strictly and effectively assumed responsibility. The three iswith responsibility, a pair of responsibility. "Two is issued safety production administration and inspection to promote the . 4), resolutely implement the safety production of the party the provisions of Hunan province safety production supervision and management responsibilities > (Hunan Zhengban made 2013 Nokers 6 people wereresolute struggle and discredit the views of the party in 2012. The style of the big consolidation activities, cadres and wor face, g major principle problems of ambiguous attitude, major issues issues of right and wrong, it cannot stand up bravely, face ton the perfect power control mechanism on "let things drift", get free in the political norms of leading cadres, some involvinay, iealistic problem of production safety as the starting point and goal of all work, to strengthen internal supervision on the wconstruction safety supervision system of "ten prohibitions", to solve the people most concerned, the most direct, the most r style trictly in accordance with the county Party committee, county government On strengthening style construction requirements and1 555 定时器的功能主要由两个比较器决定。两个比较器的输出电压控制 RS 触发器和放电管的状态。在电源与地之间加上电压，当 5 脚悬空时，则电压比较器 C1 的同相输入端的电压为 2VCC /3，C2 的反相输入端的电压为VCC 若触发输入端 TR 的电压小于VCC /3，则比较器 C2 的输出为 0，可使 RS 触发器置 1，使输出端 OUT=1。如果阈值输入端 TH 的电压大于 2VCC/3，同时 TR 端的电压大于VCC /3，则 C1 的输出为 0，C2 的输出为 1，可将 RS 触发器置 0，使输出为 0 电平。 它的各个引脚功能如下: 1脚:外接电源负端VSS或接地，一般情况下接地。 8脚:外接电源VCC，双极型时基电路VCC的范围是4.5 ~ 16V，CMOS型时基电路VCC的范围为3 ~ 18V。一般用5V。 3脚:输出端Vo 2脚:低触发端 6脚:TH高触发端 4脚:是直接清零端。当此端接低电平，则时基电路不工作，此时不论TR、TH处于何电平，时基电路输出为“0”，该端不用时应接高电平。 5脚:VC为控制电压端。若此端外接电压，则可改变内部两个比较器的基准电压，当该端不用时，应将该端串入一只0.01μF电容接地，以防引入干扰。 7脚:放电端。该端与放电管集电极相连，用做定时器时电容的放电。 在1脚接地，5脚未外接电压，两个比较器A1、A2基准电压分别为的情况下，555时基电路的功能表如表1示。 表 1 清零端 高触发端TH 低触发端 放电管T 功能 Q 导通 直接清零 0 x x 0 保持上一状态 保持上一状态 1 0 1 x 保持上一状态 保持上一状态 1 1 0 x 导通截止 置1 1 0 0 1 清零 1 1 0 3、555定时器与触发器的联系 3.1、555定时器构成单稳态触发器 the provisions of Hunan province safety production supervision and management responsibilities > (Hunan Zhengban made 2013 No. 4), resolutely implement the safety production of the party with responsibility, a pair of responsibility. "Two is issued safety production administration and inspection to promote the responsibilities bear safety production supervision departments strictly and effectively assumed responsibility. The three is the establishment of enterprise production safety hidden With self correction self reporting system, promote the enterprises to implement the main responsibility for production safety. The four is the introduction of strengthening county safety production supervision ability construction work, promote safe production responsibility to the grassroots. 3, strict accountability and target management. Adhere to the "who is in charge, who is responsible for the pipe industry must pipes, pipe production and management must control safety management business must be safe" principle, the implementation of safe production supervision and stagnation to cure. "The leadership responsible system. Production safety of key towns, key enterprises and key problems, by the township government and the Department responsible for the stagnation led the lump sum, to tackle tough. To further increase the production safety index assessment, strict implementation of safe production of "one vote veto" award and recognition system, strengthen production safety incentive mechanism (four). Adhere to the political principles against unwholesome tendencies existence of the problem is not strict internal supervision. Over the years, the global leadership team members do not have any illegal and other bad records, but there are still not strict, the implementation does not survive the problem. A few leading cadres not strictly in accordance with the county Party committee, county government On strengthening style construction requirements and style construction safety supervision system of "ten prohibitions", to solve the people most concerned, the most direct, the most realistic problem of production safety as the starting point and goal of all work, to strengthen internal supervision on the way, in the perfect power control mechanism on "let things drift", get free in the political norms of leading cadres, some involving major principle problems of ambiguous attitude, major issues issues of right and wrong, it cannot stand up bravely, face to face, resolute struggle and discredit the views of the party in 2012. The style of the big consolidation activities, cadres and workers 6 people were 图 2 上图为由555定时器和外接定时元件R、C构成的单稳态触发器。D为钳位二极管，稳态时555电路输入端处于电源电平，内部放电开关管T导通，输出端Vo输出低电平，当有一个外部负脉冲触发信号加到Vi端。并使2端电位瞬时低于1/3VCC，低电平比较器动作，单稳态电路即开始一个稳态过程，电容C开始充电，Vc按指数规律增长。当Vc充电到2/3VCC时，高电平比较器动作，比较器A1翻转，输出Vo从高电平返回低电平，放电开关管T重新导通，电容C上的电荷很快经放电开关管放电，暂态结束，恢复稳定，为下个触发脉冲的来到作好准备。波形图见图3。 图3 单稳态触发器波形图 暂稳态的持续时间Tw(即为延时时间)决定于外接元件R、C的大小。 Tw=1.1RC 通过改变R、C的大小，可使延时时间在几个微秒和几十分钟之间变化。当这种单稳态电路作为计时器时，可直接驱动小型继电器，并可采用复位端接地的方法来终止暂态，重新计时。此外需用一个续流二极管与继电器线圈并接， style trictly in accordance with the county Party committee, county government On strengthening style construction requirements andther bad records, but there are still not strict, the implementation does not survive the problem. A few leading cadres not sand o of the problem is not strict internal supervision. Over the years, the global leadership team members do not have any illegalen production safety incentive mechanism (four). Adhere to the political principles against unwholesome tendencies existence rengthduction safety index assessment, strict implementation of safe production of "one vote veto" award and recognition system, stp government and the Department responsible for the stagnation led the lump sum, to tackle tough. To further increase the prownshition to cure. "The leadership responsible system. Production safety of key towns, key enterprises and key problems, by the tomust control safety management business must be safe" principle, the implementation of safe production supervision and stagna gementet management. Adhere to the "who is in charge, who is responsible for the pipe industry must pipes, pipe production and manavision ability construction work, promote safe production responsibility to the grassroots. 3, strict accountability and targsuper plement the main responsibility for production safety. The four is the introduction of strengthening county safety productionstablishment of enterprise production safety hidden With self correction self reporting system, promote the enterprises to imthe e responsibilities bear safety production supervision departments strictly and effectively assumed responsibility. The three iswith responsibility, a pair of responsibility. "Two is issued safety production administration and inspection to promote the . 4), resolutely implement the safety production of the party the provisions of Hunan province safety production supervision and management responsibilities > (Hunan Zhengban made 2013 Nokers 6 people wereresolute struggle and discredit the views of the party in 2012. The style of the big consolidation activities, cadres and wor face, g major principle problems of ambiguous attitude, major issues issues of right and wrong, it cannot stand up bravely, face ton the perfect power control mechanism on "let things drift", get free in the political norms of leading cadres, some involvinay, iealistic problem of production safety as the starting point and goal of all work, to strengthen internal supervision on the wconstruction safety supervision system of "ten prohibitions", to solve the people most concerned, the most direct, the most r 3 以防继电器线圈反电势损坏内部功率管。 3.2 555定时器接成多谐振荡器 多谐振荡器又称为无稳态触发器，它没有稳定的输出状态，只有两个暂稳态。在电路处于某一暂稳态后，经过一段时间可以自行触发翻转到另一暂稳态。两个暂稳态自行相互转换而输出一系列矩形波。多谐振荡器可用作方波发生器。 图 4 多谐振荡器和工作波形 接通电源后，假定是高电平，则T截止，电容C充电。充电回路是VCC—R1—R2— C—地，按指数规律上升，当上升到时(TH、端电平大于)，输出翻转为低电平。是低电平，T导通，C放电，放电回路为C—R2—T—地，按指数规律下降，当下降到时(TH、端电平小于)，输出翻转为高电平，放电管T截止，电容再次充电，如此周而复始，产生振荡，经 分析 定性数据统计分析pdf销售业绩分析模板建筑结构震害分析销售进度分析表京东商城竞争战略分析 可得 输出高电平时间 T=(R1+R2)Cln2 输出低电平时间T=R2Cln2 振荡周期 T=(R1+2R2)Cln2 4 555定时器在现实生活中的应用实例 the provisions of Hunan province safety production supervision and management responsibilities > (Hunan Zhengban made 2013 No. 4), resolutely implement the safety production of the party with responsibility, a pair of responsibility. "Two is issued safety production administration and inspection to promote the responsibilities bear safety production supervision departments strictly and effectively assumed responsibility. The three is the establishment of enterprise production safety hidden With self correction self reporting system, promote the enterprises to implement the main responsibility for production safety. The four is the introduction of strengthening county safety production supervision ability construction work, promote safe production responsibility to the grassroots. 3, strict accountability and target management. Adhere to the "who is in charge, who is responsible for the pipe industry must pipes, pipe production and management must control safety management business must be safe" principle, the implementation of safe production supervision and stagnation to cure. "The leadership responsible system. Production safety of key towns, key enterprises and key problems, by the township government and the Department responsible for the stagnation led the lump sum, to tackle tough. To further increase the production safety index assessment, strict implementation of safe production of "one vote veto" award and recognition system, strengthen production safety incentive mechanism (four). Adhere to the political principles against unwholesome tendencies existence of the problem is not strict internal supervision. Over the years, the global leadership team members do not have any illegal and other bad records, but there are still not strict, the implementation does not survive the problem. A few leading cadres not strictly in accordance with the county Party committee, county government On strengthening style construction requirements and style construction safety supervision system of "ten prohibitions", to solve the people most concerned, the most direct, the most realistic problem of production safety as the starting point and goal of all work, to strengthen internal supervision on the way, in the perfect power control mechanism on "let things drift", get free in the political norms of leading cadres, some involving major principle problems of ambiguous attitude, major issues issues of right and wrong, it cannot stand up bravely, face to face, resolute struggle and discredit the views of the party in 2012. The style of the big consolidation activities, cadres and workers 6 people were 图 5 门控灯开关 该控制电路的核心是555定时器和D型触发器。555定时器接成单稳态触发器,去除触点跳动对电路工作的影响,D型触发器接成 T′触发器形式,利用其输出去控制可控硅开通和关闭,从而控制电灯的亮灭。平时当房门关闭时,安装在门扇边缘的小磁铁正好靠在干簧管旁边,干簧管的两常开触点受外磁力作用吸合,单稳态电路因输入脉冲为高电平而处于待触发状态,此时双稳态电路的输出为低电平,可控硅因无触发电流而阻断,灯不亮。当有人推门时,小磁铁会随门扇离开干簧管一次,干簧管的常开触点会因暂时失去外磁力作用而靠自身弹力张开、吸合一次。实际上,由于干簧管的触点的抖动,要重复几次这种张开、吸合的过程.单稳态触发器的 CP 端能够在干簧管的1触点第一次张开时获得一负脉冲触发信号,使单稳态触发器翻转为暂稳态,其输出由低电平变为高电平此时,电容器 C 经 R 充电,复位端 R 电位上升,当上升到复位电平2/3V 时,单稳态触发器复位,Q 恢复为低电平。 单稳态电路的时间常数 T=1.1R C ,它有效地将干簧管的具有抖动信号现象的脉冲信号展宽为单个脉冲,此正脉冲同时加至 T′触发器器的 CP2端,其输出由低电平变为高电平,可控硅的控制极获得正向触发电流而导通,电灯通电发光.当进来的人离开时,随着门的再一次打开、关闭,干簧管重复同样的动作,单稳态触发器同样输出一正脉冲信号,于是T′触发器再次翻转为低电平,可控硅失去触发电流并在交流电过零时关断,电灯自动熄灭。光敏电阻 R 和可调电阻 R 构成光控电路。在白天 ,光敏电阻受自然光照射阻值很小 ,T′触发器的置“0”端 R电位 >1/2V ,无论此门被开闭多少次 ,DD电路强制置“0”,Q始终为底电平 ,电灯不会发光;夜晚 ,因自然光照减弱 ,T′触发器的置“0”端 R 电位 <1/2V ,强制复位自动解除。 实际应用时,将开关盒安装在门框顶上,小磁铁则正对着盒内底侧部放置的干簧管固定在门扇顶沿上。仔细调整小磁铁和干簧管的相对位置,使干簧管能够随门扇的开闭而可靠地动作。 ther bad records, but there are still not strict, the implementation does not survive the problem. A few leading cadres not sand o of the problem is not strict internal supervision. Over the years, the global leadership team members do not have any illegalen production safety incentive mechanism (four). Adhere to the political principles against unwholesome tendencies existence rengthduction safety index assessment, strict implementation of safe production of "one vote veto" award and recognition system, stp government and the Department responsible for the stagnation led the lump sum, to tackle tough. To further increase the prownshition to cure. "The leadership responsible system. Production safety of key towns, key enterprises and key problems, by the tomust control safety management business must be safe" principle, the implementation of safe production supervision and stagna gementet management. Adhere to the "who is in charge, who is responsible for the pipe industry must pipes, pipe production and manavision ability construction work, promote safe production responsibility to the grassroots. 3, strict accountability and targsuper plement the main responsibility for production safety. The four is the introduction of strengthening county safety productionstablishment of enterprise production safety hidden With self correction self reporting system, promote the enterprises to imthe e responsibilities bear safety production supervision departments strictly and effectively assumed responsibility. The three iswith responsibility, a pair of responsibility. "Two is issued safety production administration and inspection to promote the . 4), resolutely implement the safety production of the party the provisions of Hunan province safety production supervision and management responsibilities > (Hunan Zhengban made 2013 Nokers 6 people wereresolute struggle and discredit the views of the party in 2012. The style of the big consolidation activities, cadres and wor face, g major principle problems of ambiguous attitude, major issues issues of right and wrong, it cannot stand up bravely, face ton the perfect power control mechanism on "let things drift", get free in the political norms of leading cadres, some involvinay, iealistic problem of production safety as the starting point and goal of all work, to strengthen internal supervision on the wconstruction safety supervision system of "ten prohibitions", to solve the people most concerned, the most direct, the most r style trictly in accordance with the county Party committee, county government On strengthening style construction requirements and5 然后,根据“火线接开关地线进灯头,接通开关和灯头”的照明灯接线原则,将开关盒内桩头外引线不分顺序串入电灯火线回路即可。 最后,用小螺丝刀将 R 调至阻值最小的位置,P在夜晚需要开灯的时候,打开门扇使灯点亮,然后由小到大调节R 阻值,直到电灯刚好熄灭,再将 R 阻值回调一点即可.反复细调,即可获得最佳光控灵敏度。 5 结论 555 定时器把模拟电子中的放大功能和数字子的逻辑功能融合起来 ,定时精确 ,电源范围宽直接推动负载.因此 ,作为一种价格低廉、性能优使用方便的中规模的集成电路 ,555 定时器已成数字电路中最常用的时基电路之一 ,必将在控制域得到更广泛的应用. the provisions of Hunan province safety production supervision and management responsibilities > (Hunan Zhengban made 2013 No. 4), resolutely implement the safety production of the party with responsibility, a pair of responsibility. "Two is issued safety production administration and inspection to promote the responsibilities bear safety production supervision departments strictly and effectively assumed responsibility. The three is the establishment of enterprise production safety hidden With self correction self reporting system, promote the enterprises to implement the main responsibility for production safety. The four is the introduction of strengthening county safety production supervision ability construction work, promote safe production responsibility to the grassroots. 3, strict accountability and target management. Adhere to the "who is in charge, who is responsible for the pipe industry must pipes, pipe production and management must control safety management business must be safe" principle, the implementation of safe production supervision and stagnation to cure. "The leadership responsible system. Production safety of key towns, key enterprises and key problems, by the township government and the Department responsible for the stagnation led the lump sum, to tackle tough. To further increase the production safety index assessment, strict implementation of safe production of "one vote veto" award and recognition system, strengthen production safety incentive mechanism (four). Adhere to the political principles against unwholesome tendencies existence of the problem is not strict internal supervision. Over the years, the global leadership team members do not have any illegal and other bad records, but there are still not strict, the implementation does not survive the problem. A few leading cadres not strictly in accordance with the county Party committee, county government On strengthening style construction requirements and style construction safety supervision system of "ten prohibitions", to solve the people most concerned, the most direct, the most realistic problem of production safety as the starting point and goal of all work, to strengthen internal supervision on the way, in the perfect power control mechanism on "let things drift", get free in the political norms of leading cadres, some involving major principle problems of ambiguous attitude, major issues issues of right and wrong, it cannot stand up bravely, face to face, resolute struggle and discredit the views of the party in 2012. The style of the big consolidation activities, cadres and workers 6 people were