# 500 Watts DC to DC Power Converter

Status
Not open for further replies.

#### lmartinel

##### New Member
I have been working on a 500 watts DC to DC power Converter. I am utilizing a push pull configuration to drive a high frequency switching transformer. However, the chip that I am using for driving the mosfets doesn't have the features such as shut down or current limiting. It does provide the ability to PWM and the frequency can be set up by an external capacitor and resistor. Does any one know of a chip that has a shut down, current limiting, PWM, feedback, and soft start features for a push pull DC to DC converter. It will be for a 170 DC voltage converter on the output. Thank you

#### dknguyen

##### Well-Known Member
Are you using an MCU? If you are, you might prefer to add on a few extra components (comparators and such) and have the MCU do that stuff itself. I find the gate drivers with built-in current limiting have strange wiring schemes that are limiting in functionality.

#### lmartinel

##### New Member
No, I am not using a micro controller U. I am using a good old ancient TL598 PWM chip and a few other components to do the job. I have been out of school for a while. However, I would not have a clue on where to start with a MCU. However, If you may direct me into the path of learning how to utilize a MCU, I would not be afraid to learn it. I am good programmer when it comes to c and c++. So if there is a MCU that could be programmed by such language, please advice of it and I will take a look at it. Thank you for your prompt response

#### dknguyen

##### Well-Known Member
Well you need a microcontroller, it's datasheet, a compiler and a programmer (a piece of hardware and software that sits between the MCU and the PC to upload code onto it).

Everything is controlled by writing values to registers (they appear to you as pre-defined variable names in the compiler and they are all in the datasheet) . Like if you try to send a message over a UART, you might write the thing you want to send into a register and then you might set a bit in another register to send so you do that.

Good starts are PIC or Atmel becaues of the availability of free compilers and cheap programmers (the extreme cost of many development tools are what seems to limit many people in the choice of microcontroller or processor). I've just recently found out that ARM 7 and ARM Cortex-M3 processors are the same way.

Last edited:

#### tcmtech

##### Banned
what voltage are you using for the source?

#### ronsimpson

##### Well-Known Member
Because you know the TL598, try the UC1846. It has current limit and shutdown.

#### stefanodel

##### New Member
I have been working on a 500 watts DC to DC power Converter. I am utilizing a push pull configuration to drive a high frequency switching transformer. However, the chip that I am using for driving the mosfets doesn't have the features such as shut down or current limiting. It does provide the ability to PWM and the frequency can be set up by an external capacitor and resistor. Does any one know of a chip that has a shut down, current limiting, PWM, feedback, and soft start features for a push pull DC to DC converter. It will be for a 170 DC voltage converter on the output. Thank you
Using few external components, you get the features you require. You can take a look at this TI application note:
http://www.electro-tech-online.com/custompdfs/2009/03/slva003b.pdf

Stefano

#### lmartinel

##### New Member
what voltage are you using for the source?
It will be 12v Pulses on the primary side of the high frequency switching transformer. The primary side of the transformer is set up in a push pull configuration.

#### lmartinel

##### New Member
Because you know the TL598, try the UC1846. It has current limit and shutdown.
Thank you very much. I looked at the specifications for the UC1846 and it appears that it will do what I am looking for.

#### tcmtech

##### Banned
Once again I will probibly be over simplifing something.

Why not use a factory made inverter? They take 12 volts and step it up to 170 volts before turning it into AC output.
Plus the better ones have all the features you are looking for, plus they go for cheap on ebay for used or damaged ones.
I ocasionaly pick up broken units, fix them and resell them localy to people I know.

A good 1500w burned out unit can go for less than $20. Repair costs usualy are under$30 and I can resell it for $100. Plus every one I have ever bought burned out either had the switching mosfets on the input blown or the output h-bridge blown. Just a thought. #### lmartinel ##### New Member Ebay is a good place to buy products. However, I get more enjoyment in designing my own electrical devices. #### tcmtech ##### Banned Most Helpful Member Ah... Just for the fun of it! You now have my full support! Still a cheapy factory made is a good parts source for the odd transformers and bits and pieces. Ive done a couple of just fore fun mods on cheap inverters too. Changing the output voltages and what not. Good luck and have fun! #### lmartinel ##### New Member Ah... Just for the fun of it! You now have my full support! Still a cheapy factory made is a good parts source for the odd transformers and bits and pieces. Ive done a couple of just fore fun mods on cheap inverters too. Changing the output voltages and what not. Good luck and have fun! I will definitely take your advice and keep and eye on those broken power inverters on eBay. I sure can use some copper wire for building those high frequency switching transformers. Thank you #### tcmtech ##### Banned Most Helpful Member If your looking for good high quality enamaled copper wire in various sizes find a local electric motor repair shop. They buy in bulk and will resell to any one.$8 a pound last time I checked localy.
They got loads of bits and pieces too! probibly get a hand full of 5 ft and under cut offs just for asking. Its way easier and cleaner than trying to reuse old windings.

Status
Not open for further replies.