CIRCUIT DIAGRAM FOR PULSE
In astable mode, the 555 timer puts out a continuous stream of rectangular pulses having a specified frequency. Resistor R1 is connected between VCC and the discharge pin (pin 7) and another resistor (R2) is connected between the discharge pin (pin 7), and the trigger (pin 2) and threshold (pin 6) pins that share a common node.
Hence the capacitor is charged through R1 and R2, and discharged only through R2, since pin 7 has low impedance to ground during output low intervals of the cycle, therefore discharging the capacitor.
If want use pulse to combine with other circuit, remove the LED and R2. Connect leg number 3 and ground to other circuit.
LIST OF THE COMPONENT
HA17555 CIRCUIT DIAGRAM
The flip-flop RS latch use for this circuit diagram.
