Battery operated switched mode power supply questions.

[Leosedf]

Hello!
I would like to use a high discharge rate Li-Ion Cell (3.7V) and design an adjustable power supply, my requirements are:
1-10V output voltage.
If possible up to 10A. (i realise that may not be possible when my output is high voltage)
Load resistance from 0.2 or 0.5Ω up to 3Ω.
Smallest possible size since it's portable.


I was wondering which is better, use a dc-dc step up to raise my voltage up to 12V and then use a mosfet with PWM to trimm down the voltage or use an adjustable dc-dc?
I will have a pic microcontroller available.
Linear technology has some very small dc-dc converters but i am not sure which path to follow.

What do you guys think?

 

[deepeshmishra]

Hello!
I would like to use a high discharge rate Li-Ion Cell (3.7V) and design an adjustable power supply, my requirements are:
1-10V output voltage.
If possible up to 10A. (i realise that may not be possible when my output is high voltage)
Load resistance from 0.2 or 0.5Ω up to 3Ω.
Smallest possible size since it's portable.


I was wondering which is better, use a dc-dc step up to raise my voltage up to 12V and then use a mosfet with PWM to trimm down the voltage or use an adjustable dc-dc?
I will have a pic microcontroller available.
Linear technology has some very small dc-dc converters but i am not sure which path to follow.

What do you guys think?

You can use Ic 34063api A"dc to dc converter "
It is quite simple also

 

[Leosedf]

MC34063 Is a 1.5A switching regulator. It would be one of the worst choices for this.

 

[deepeshmishra]

It is clearly mentioned in the datasheet of MC34063 how to increase your current ratings.

 

[bill66656]

Are you sure you want to give 10A out at 10V? You need more than one batteries to be used in parallel. Not only from current but also from power level angel.

 

[Leosedf]

Well my output requirements are around 7-10 seconds.

I am using high drain IMR batteries.


Other supplies work at 5-6A without a problem (off course draining the battery a lot) but that's what i want.
I do not plan to go below 3.2-3.3V (way above the 2.750v cut off)