buck boost converter design with 555 simulation

Thread Starter

angelo123123123

Joined Sep 29, 2019
2
hey. can somebody help with my project, i need to make a buck-boost converter using electronic workbench, i dont know how to power the mosfet using 555 or any components. thanks.
 

DarthVolta

Joined Jan 27, 2015
521
Welcome, Well if you're really new, the 555 would be set up to make the on/off pulse signal going to the gate of the mosfet. Typically for lowside nmos, I see a very small resistor, like 2.2 to 22 ohms resistor, from the pulse width modulation output, to the gate, and to a 10k ohm resistor to GND. That combines with the gate capacitance to makes a filter circuit.

As for a good 555 circuit for PWM, I'm not sure myself, I used 1 lately, but didn't take the time to understand how it worked.
 

Thread Starter

angelo123123123

Joined Sep 29, 2019
2
Welcome, Well if you're really new, the 555 would be set up to make the on/off pulse signal going to the gate of the mosfet. Typically for lowside nmos, I see a very small resistor, like 2.2 to 22 ohms resistor, from the pulse width modulation output, to the gate, and to a 10k ohm resistor to GND. As for a good 555 circuit for PWM, I'm not sure myself, I used 1 lately, but didn't take the time to understand how it worked.
thank you very much for the response. can you send visual aid to help me understand more about it and then ill try if i can make it to electronic workbench.
 

Andrei Suditu

Joined Jul 27, 2016
52
hey. can somebody help with my project, i need to make a buck-boost converter using electronic workbench, i dont know how to power the mosfet using 555 or any components. thanks.
555 can gen pwm but you would need a hell lot of other things.
Try with a tl494.
You need to adjust pwm duty based on current draw and try to keep the current in the inductor above 0.
Tl494 datasheet has a few examples.
 
Top