Help to design step down converter (urgent)

[alihussien]

please I am asked to design step down converter with input voltage 48_V and the out voltage desired to be 24_V ,12_V ,5_V
I need any useful circuits , links or soures and thank you

 

[eiphan]

Are you going to use Microcontroller for design or Buck converter chip? the chip such as LM2825 can perform as buck converter. There are many more chip available.

 

[jerry12]

How about simple Voltage divider?

 

[nitishn5]

A Voltage Divider Would be awesomely inefficient.

You should try a multi-winding Buck converter.
It should have 3 secondary windings one for each 24V, 12V and 5V. Put the feedback control on one of the outputs say the 24V to regulate that one. Design the other outputs to give say 15V and 8V and use 7812 and 7805 to regulate them.

I have done this for a 230Vac to 5V, +12V, -12V converter.

 

[Tahmid]

please I am asked to design step down converter with input voltage 48_V and the out voltage desired to be 24_V ,12_V ,5_V
I need any useful circuits , links or soures and thank you

You haven't mentioned the required current/power.

If it's going to be only for reference, a voltage divider would do. You may look into adding a buffer at the output of the voltage divider.

However, if it's going to be used to loads (at greater than, for example, 200mA), you should look into using a switching regulator or a DC-DC converter block. You can use many of the readily-available switching regulator chips offered by ST, TI, LT among others. You can use a microcontroller or general purpose PWM controller and make your own regulator using a buck converter. You may design a flyback convert as well.

There are many options available and which you use will depend on the required power and cost/complexity of circuit desired.

Hope this helps.
Tahmid.