LM555/NE555/SA555 Single Timer
LM555/NE555/SA555 7 The equivalent circuit for discharging capacitor C1 when timer output is low as follows: Since the duration of the timer output low state(tL) is the amount of time it takes for the VC1(t) to reach Vcc/3,Since RD is normally RB>>RD although related to the size of discharging Tr.,
