SN76604说明书
特点
测试电路
内部电原理图
1
fI
putcircuit输入电路becauseofa
i
tegratedi
vertertheSN76604ca
bedrive
from
egativeorpositivegoi
gpulsesarefedi
tothei
verteratpi
1a
dpi
2a
d3haveto3havetobetiedtogetherthetriggerlevelforthepulsesis1voltSN76604是一个从正面或负面的脉冲驱动集成正反电路,脉冲送入引脚1,引脚2和3的需连在一起。脉冲触发电平1V。Negativevoltagepulseshavetobecoupledcapacitivelyasshow
i
fig2负电压脉冲被电容耦合,如图所示。thepulseamplitudethe
hastobe45voltspeakpeakwith48Vsupply脉冲幅度则是45伏峰峰值与48V供给。refere
cepulsecircuit参考脉冲电路
theexter
alsetupfortherefere
cepulsecircuitisshow
i
fig3外部设置参考脉冲电路如图3所示。Therefere
cepulsewidthofthemo
ostableisgive
bytheequatio
这个单稳态参考脉冲宽度由下式给出:To
09R1C1Vp07VccwhereVpisthevoltageatthewiperoftheservopote
tiometerVP是伺服电位器抽头电压。Forcorrectfu
ctio
followi
glimitsshouldbeobserved正确的功能应遵循以下限制R4ca
beomittedifitise
suredthatthewipervoltage
everdecreasesbelow1voltegifthemotorshaftrotatio
ismaximum180a
da270pote
tiometerisusedR4可以确保舵机电压不低于1伏,略如。如果电机轴旋转是最大的1800和2700的电位差计。themi
imumtimeperiodfromo
ei
putpulsetothe
exto
eisdefi
edbytheRCtimeco
sta
tofthechargi
gcircuitwhichishighestwiththewiperi
midpositio
Forhighdutycyclesthereforealowimpeda
cepote
tiometershallbeusedthemi
imumperiodbetwee
i
putpulsesis:
2
f从一个输入脉冲到下一个最小的时间段是指由RC时间常数的充电电路,最高在中间位置的雨刮器高占空比因此应使用一个低阻抗电位器。输入脉冲之间的最小周期是:Toff10xR0C1R0istheequivale
tchargi
gresista
cedefi
edbyR2R3R4a
dRBEQ31R0等效充电电阻通过定义R2,R3,R4和RBEQ31Choosi
gR1maximum12Ka
dR2mi
imum15100dutycycleispossible选择R1和R2最大(12K)最小(15)100工作周期是可能的。Variatio
sofrefere
cepulsewidthwithrespecttosupplyvoltagecha
gesareelimi
ateda
d参考脉冲宽度随电源电压变化的变化被消除TTVccvcc02Thetemperaturecoefficie
toftherefere
cepulsewidthisgive
bytheTCofR1C1参考脉冲的宽度的温度系数TC是由R1,C1决定。I
ordertoavoidjitteroftherefere
cepulsetheoutputspi
1113mustbeloadedwithatleast1K。为了避免参考脉冲的输出抖动(引脚1113)必须有至少1k的阻值deadBa
d死区Thepurposeofthedeadba
distoavoidmotorboati
gthedeadba
dismadebyshorte
ir