This is an Active buzzer is present inside with shock source, so as long as the electricity will call 2 Program control convenient, single chip microcomputer a high and low level can make the sound, and the passive buzzer is can not do.
The SI4450DY, SI4450, SI-4450,4 450 is a 60V 7.5A 2.5W This N-Channel MOSFET is produced using Fairchild Semiconductor's advanced Power Trench process that has been especially tailored to minimize on-state resistance & yet maintain superior switching
The MT3608 Step-up converter (Output voltage higher than input). Supply voltage 2-28V, output max. 28V at max 2A. Avoid the state when the input terminals have higher voltages than those set on the output terminals. The drive chip may be damaged.
The MJH6284G, MJH6284, 6284 is a – 100V 20A 4MHz 160W NPN - Darlington Bipolar Transistor Through Hole TO-218 from ON Semiconductor. MJH6284(NPN), MJH6287(PNP) Darlington Complementary Silicon Power Transistors.