
555功能表
4脚 | 5脚 | 2脚 | 6脚 | 3脚 |
低电平 | 任意 | 任意 | 任意 | 低电平 |
高电平 | Vct | 任意 | 高电平 | |
高电平 | Vct | >Vct | 低电平 | |
高电平 | Vct | <Vct | 保持 |
A.干簧管闭合时,V6导通 |
B.增大R6,减小下雨时关窗信号的设定值 |
C.傍晚V5始终不发光,应增大R8 |
D.Rl是湿敏电阻,阻值随湿度的增大而减小 |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

