LM2586 booster regulator help

[RockStar]

Hello everyone!

I am having an issue with the lack of current from this circuit and wondering if you have any suggestions. I built this booster circuit to power an amp that is rated from 40-50 volts DC. Using the the LM2586T- Adj put me right into the rang of 12 volts input with 48volts out. The issue, this circuit is only good for .8 amps of current. I need this circuit to hold at least 20amps. I though about using a set of pass transistors to hold the current but I am not sure if that work? I have built many step down regulators to hold as much as 200amps @ 12volts however this step up business seems backwards to me. Any help would great!!

thanks again!

Here is the diagram I am working with...

**broken link removed**

 

[Ubergeek63]

never happen... you have a 3A switch, divided by the transfer ratio to give you the 0.8A

you need to be switching 100A@12V to get 20A@48V

dan

 

[RockStar]

is there anyway to "beef-up" this circuit using a series of pass transistors?

 

[blueroomelectronics]

Your source (a 12 car battery?) will need to supply at least 100A continuously, this would melt a typical car battery. What do you need 48V @ 20A for?

 

[crutschow]

A totally annoying (and deaf inducing) sound system for a car?

 

[blueroomelectronics]

Oh can we guess? How about a pointless and inefficient HHO power supply.

 

[smanches]

You need to use a boost regulator with external switches. This one has it's own internal switch, so there is no way to increase it's performance easily.

 

[RockStar]

You need to use a boost regulator with external switches. This one has it's own internal switch, so there is no way to increase it's performance easily.

Thanks Smanches! I am curious about the external switches for this boost application. Do you have any examples or somewhere I can reference this type of circuit in greater detail?

I am using this “boost circuit” to achieve the acquired voltage from a standard car voltage source, basically 12volt in and 48 out to power a 10 meter ham radio amplifier @ 20 amps continuous duty cycle. As far as the amperage on the 12volt source, this is not a problem

 

[schmitt trigger]

For this power level, you really need a full-bridge driver.