Hello All,

I tried to simulate to buck-boost for below requirement.

Vin = 2.5V-4.2V
Vout = 3.3V @500mA
Fsw = 250KHz

Could anybody help me where my simulation file is wrong ?

Thanks in Advance !

 

What is wrong with it?

 

V1 is the voltage source name, but the source doesn't have a voltage value.

 

hi mishra,
This is your modified circuit, uses a 1A Schottky diode and 7R Load.
E
BTW: the BAT was the wrong way around for a +Vout.

 

hi mishra,
This is your modified circuit, uses a 1A Schottky diode and 7R Load.
E
BTW: the BAT was the wrong way around for a +Vout.

Thanks for your reply !

If Vbat = 2.5V, how can i get Vout = 3.3V@500mA ?
If Vbat = 4.2V, how can i get 3.3V @500mA ?

My objective is design buck-boost to meet above requirement. I wanted to see boost behavior at 2.5V & Buck behavior at 4.2V.
Please share LT Spice file

I hope the requirement is clear to all of you ?

Thanks in Advance !

 

hi mishra,
This is your modified circuit, uses a 1A Schottky diode and 7R Load.
E
BTW: the BAT was the wrong way around for a +Vout.

In attached schematic diode placed wrong as per my understanding.

 

hi,
Look at this version of a sepic converter that uses LT3757 , but it should be help in designing your own circuit.

E

 

hi mishra,
Watch this video.
E