Hello,
i need to output 35 V output to control a mosfet (high Side).
i have 4 battery (6V each) and i have LM2575-5 and LM2575-15 regulator already in the scheme, the max current won't matter,its less than 100mA

is there any circuit that can boost 35V from 24V?
will the LM2577-adj works ?

thanks

 

Why don't you simply use a high-side MOSFET gate driver IC? You'll get much better performance than if you tried to cobble something together out of discrete parts, and your PCB footprint will be smaller.

For an example, look at the TC4431 (inverting) and TC4432 (noninverting) high-side gate drivers that Microchip makes. They're available in 8-pin DIP packages.

 

Why don't you simply use a high-side MOSFET gate driver IC? You'll get much better performance than if you tried to cobble something together out of discrete parts, and your PCB footprint will be smaller.

For an example, look at the TC4431 (inverting) and TC4432 (noninverting) high-side gate drivers that Microchip makes. They're available in 8-pin DIP packages.

Hi,
i wish i can get mosfet drivers.... they're not available in algeria,so i had to make my custom driver

 

Is the output voltage critical?

One thing you can try is a capacitive voltage doubler. You can build one around an oscillator and a capacitor, and a zener to clamp it at 35V. Since you're driving MOSFETs, the small capacitive charge pumps are probably not an option.

 

Do you have any more of these LM2575 IC's? If so, which do you have?

Have you ever wound your own inductors or transformers before?

Do you have an oscilloscope?

Have a look at Ronald Dekkers' "Flyback Converters for Dummies" page. It's a good intro on making your own from items you can salvage.
http://www.dos4ever.com/flyback/flyback.html
Basically, you can use one of those LM2575 IC's with a transformer on the output instead of a simple inductor, along with some creative use of feedback resistors, to turn those buck IC's into a flyback converter.