DIY 555 Timer (Transistorized)

Hello amigos!

This 555 timer only uses NPN, PNP BJT TO-92 transistors, and a few 0.5w precision resistores (24 transistors and 17 resistors in total). it works like a charm. and on the back side of the pcb there are a few usfeul schematics that shows how to connect the 555 timer in astable or monostable configuration.

also a few usfeul equations to calculate: output frecuency, duty cycle, period, time high (PWM) and time low, etc.

you can energize it from 5v up to about 20v DC, and it has three main test points: tp1, tp2, and tp3. in what you can measure the voltaje values in each step of 1/3 of total voltaje from external capcacitor, and the 2/3 of othe total input voltage, like: 0V, 0.6V, 1.4V, 0.2V and so on. 

and the best part this is high current and high reparable 555 timer that you can use in school basic digital electronic practices, repairable, and you'll learn how a 555 internally works.

This project is Open source so you can download it for free for personal or educative uses. i include the gerber files, schematic diagram, 2D model, 3D model, BOM, and Pic and Place files, with a few pictues, this project is fully testted and fully functional.

Also any donation is wecomed that you can send me trough my PayPal account: @electromanmx 

So i can make more interesting and useful electronic projects 🙂

Thank you for reading !