#10 second timer ic driver#

This allows the capacitor CD to charge via the timing resistor RD until the voltage across CD reaches 2/3rd supply level or Vcc.Īs soon as this happens the R/S flip flop reverts to its previous state, switching ON Q6 and causing a quick discharge of CD. With Q6 switching OFF disconnects the short across CD. This 0V pulse being below the 1/3rd level of the DC supply voltage or the Vcc, forces the output of the trigger comparator to change state.ĭue to this, the R/S flip-flop also changes its output state, turning off Q6 and driving OUTPUT pin 3 high.

The standard Timer action of the IC 555 is initiated by introducing a 0 V trigger pulse at pin 2.

In this situation, Q6 remains saturated, which keeps the external timing capacitor CD shorted to ground, causing the OUTPUT pin 3 is to be at a low logic or 0 V level. When IC 555 is configured in the monostable timer mode, the TRIGGER pin 2 is held at the supply level potential through an external resistor RT. The output state of the flip flop can be also set by triggering the reset pin 4 of the IC.

#10 second timer ic driver#

With these trigger inputs the two op amps control the R/S (reset/set) flip flop stage, which further control the ON/OFF conditions of the complementary output stage and the driver transistor Q6 The stage involving the three 5 kohm resistors work like a voltage divider stage which produces 1/3rd voltage level at the non-inverting input of the trigger comparator op amp and a 2/3 voltage division on the inverting input of the threshold comparator op amp.