The 555 time base circuit can be used to form various types of self-excited multivibrators. The basic circuit is shown in Figure a. When the circuit is just turned on, since C is too late to charge, the 2 pin of the 555 circuit is at zero level, causing its output 3 pin to be high. When the power supply is charged to Cc to Vcc through RA and RB, the output terminal 3 is changed from the high circuit to the low level, and the capacitor C is discharged through the RB and the discharge switch of the internal circuit. When discharging to Vc ≤ Vcc, the output is converted from a low level to a high level. At this point, the capacitor is recharged, and this process can be repeated to form a self-oscillation. Figure (b) shows the waveform of the voltage at the output and capacitor C. This process can be carried out in a continuous manner to form a self-oscillation. Figure (b) shows the waveform of the voltage at the output and capacitor C. 555 multivibrator basic circuit related waveform New from Puff Bar comes the Puff Plus Disposable Vape pen. The pens are pre-filled with 3-5mL of 5%(50mg) nicotine e-juice. The device has a 550-650mAh internal battery that`ll last you for the entire 3.2mL of juice. This effectively doubles the life of the classic Puff Bar pens. The device is larger than the original, and now takes on a cylindrical shape. No need to charge or refill, these draw-activated pens can be disposed of when they're spent. Disposable Vape 900 Puffs,900 Puff Vape,900 Puff E Cig,Disposable Vape Pen 900 Puffs Nanning Goodman Technology Co.,Ltd , https://www.goodmentech.com