DIY-LED Heart-Shaped Simple Flash Circuit

From the schematic diagram can be seen, 18 LED is divided into three groups, whenever the power is connected, the three transistors will lead the first conduction, but due to differences in components, only one transistor first conduction, Q1 is the first conduction, then the LED1 this group is lit, due to Q1 conduction, the collector voltage drop makes the capacitor C2 left end down, close to 0V, because the voltage across the capacitor can not be changed, so the base of Q2 is also pulled to approximate 0V, Q2 cut off, so connected to its collector LED2 this group of. At this point Q2 high voltage through the capacitor C3 to Q3 collector voltage, Q3 will quickly turn on, LED3 this group lit. So in this period of time, Q1, Q3 of the collector are low, LED1 and LED3 these two groups are lit, LED2 this group extinguished, but with the power through the resistor R2 on the C2 charge, Q2 base The voltage gradually increases, when more than 0.7V, Q2 from the state to the conduction state, the collector voltage drop, LED2 this group is lit. At the same time, the voltage drop of the collector of Q2 is reduced by the capacitance C3, so that the base voltage of Q3 is also reduced, Q3 is turned from on to its collector voltage, and LED3 is extinguished. Next, in the circuit in accordance with the process described above cycle, three groups of 18 LED will be turned light, the same time there are two groups of 12 LED is lit. These LEDs are cross-arranged in a heart-shaped pattern, the continuous cycle of flashing light, to achieve the effect of a dynamic display.

Kit includes: