驱(qu)动(dong)电(dian)(dian)压10V,驱(qu)动(dong)信号(hao)为(wei)PWM波,占空比为(wei)50%,频(pin)率为(wei)1Mhz,寄(ji)(ji)生(sheng)电(dian)(dian)感(gan)10nH,MOS管...驱(qu)动(dong)电(dian)(dian)压10V,驱(qu)动(dong)信号(hao)为(wei)PWM波,占空比为(wei)50%,频(pin)率为(wei)1Mhz,寄(ji)(ji)生(sheng)电(dian)(dian)感(gan)10nH,MOS管寄(ji)(ji)生(sheng)电(dian)(dian)容为(wei)1nF,栅(zha)极串(chuan)联(lian)电(dian)(dian)阻(zu)为(wei)20Ω,这个电(dian)(dian)阻(zu)消耗的功率是(shi)多大?
由于(yu)换能器(qi)发(fa)出的(de)(de)(de)超声波前辐(fu)射面声压同施加电压对时间(jian)的(de)(de)(de)导数dU/dt成正比,尽量...由于(yu)换能器(qi)发(fa)出的(de)(de)(de)超声波前辐(fu)射面声压同施加电压对时间(jian)的(de)(de)(de)导数dU/dt成正比,尽量缩短激(ji)励脉(mai)冲(chong)上(shang)升时间(jian)至关重(zhong)要。激(ji)励脉(mai)冲(chong)的(de)(de)(de)上(shang)升时间(jian)主要取决于(yu)MOS管(guan)的(de)(de)(de)导通速度。
过(guo)冲(chong)(chong)(chong)和下(xia)(xia)冲(chong)(chong)(chong)原(yuan)理是(shi)一(yi)(yi)样的,这里以(yi)(yi)过(guo)冲(chong)(chong)(chong)为(wei)例(li)子分析(xi)。上面mos管(guan)打(da)开的瞬间(jian),可(ke)以(yi)(yi)等(deng)...过(guo)冲(chong)(chong)(chong)和下(xia)(xia)冲(chong)(chong)(chong)原(yuan)理是(shi)一(yi)(yi)样的,这里以(yi)(yi)过(guo)冲(chong)(chong)(chong)为(wei)例(li)子分析(xi)。上面mos管(guan)打(da)开的瞬间(jian),可(ke)以(yi)(yi)等(deng)效为(wei)上图开关闭合(he)的瞬间(jian)。可(ke)以(yi)(yi)理解给(ji)了一(yi)(yi)个(ge)阶跃信号,因(yin)此(ci)电(dian)压过(guo)冲(chong)(chong)(chong)是(shi)该(gai)RCL电(dian)路(lu)对阶跃...
在推挽式(shi)驱动结(jie)构中(zhong)(zhong),当(dang)互补MOSFET开启时,正(zheng)常(chang)情(qing)况(kuang)下(xia)漏(lou)极电(dian)(dian)(dian)压(ya)(ya)会升至(zhi)直流(liu)电(dian)(dian)(dian)源(yuan)电(dian)(dian)(dian)...在推挽式(shi)驱动结(jie)构中(zhong)(zhong),当(dang)互补MOSFET开启时,正(zheng)常(chang)情(qing)况(kuang)下(xia)漏(lou)极电(dian)(dian)(dian)压(ya)(ya)会升至(zhi)直流(liu)电(dian)(dian)(dian)源(yuan)电(dian)(dian)(dian)压(ya)(ya)的(de)两倍(或者本例(li)中(zhong)(zhong)的(de)30V)。然而,如图1所示,尖峰电(dian)(dian)(dian)压(ya)(ya)却高(gao)达54V。在MOSFET关闭以...
为了降(jiang)低开关(guan)节点产(chan)(chan)生的(de)尖峰(feng)电(dian)(dian)压,可考(kao)虑(lv)增加RC缓冲(chong)电(dian)(dian)路(lu)。在(zai)(zai)下(xia)面的(de)示(shi)例(li)中(zhong),整流(liu)...为了降(jiang)低开关(guan)节点产(chan)(chan)生的(de)尖峰(feng)电(dian)(dian)压,可考(kao)虑(lv)增加RC缓冲(chong)电(dian)(dian)路(lu)。在(zai)(zai)下(xia)面的(de)示(shi)例(li)中(zhong),整流(liu)二极管(guan)关(guan)断(高边(bian)开关(guan)导通)时(shi),RC缓冲(chong)电(dian)(dian)路(lu)可将二极管(guan)的(de)接合(he)部、寄生电(dian)(dian)感(gan)、寄生电(dian)(dian)容...
保(bao)(bao)证开(kai)(kai)(kai)关(guan)(guan)管在(zai)开(kai)(kai)(kai)、关(guan)(guan)过程(cheng)中(zhong)du/dt、di/dt足够小,限制(zhi)开(kai)(kai)(kai)关(guan)(guan)管上(shang)的电(dian)(dian)压(ya)或电(dian)(dian)流峰(feng)值,...保(bao)(bao)证开(kai)(kai)(kai)关(guan)(guan)管在(zai)开(kai)(kai)(kai)、关(guan)(guan)过程(cheng)中(zhong)du/dt、di/dt足够小,限制(zhi)开(kai)(kai)(kai)关(guan)(guan)管上(shang)的电(dian)(dian)压(ya)或电(dian)(dian)流峰(feng)值,从而保(bao)(bao)证开(kai)(kai)(kai)关(guan)(guan)管正确(que)可靠地运行;并降(jiang)低EMI的水平。