555电路组成的无稳态标准电路(图1),3脚输出的方波信号,起始为高电平,且第一个脉冲时间比后面的脉冲时间长57%。如果把C_1的接地端改接到5脚上,可克服上述缺点,从该电路取得锯齿波信号有两个途径:一是由3脚输出,但须经波形变换;二是把 555 circuit composed of non-steady-state standard circuit (Figure 1), 3 feet square wave signal output, starting high, and the first pulse time 57% longer behind the pulse. If the C_1 ground connected to the 5-pin to overcome the above shortcomings, the sawtooth signal obtained from the circuit in two ways: First, the output by the 3 pin, subject to waveform conversion; the second is to