HH004F LED driver

HH004F LED driver circuit

HH004F is a low power integrated boost converter IC in a TO-92 package, look exactly like a small transistor. Though it's quite a uncommon and undocumented IC, but you may…
Stable miniature FM transmitter circuit

Stable miniature FM transmitter circuit

FM transmitter circuit projects are indeed quite popular among electronics hobbyists/students. But the frustrating part is most transmitters refuses to work at all, and secondly the internet is full of crappy…