• 12 Volt Dc Motors
• How To Make 18 Volt Dc 12 Volt Dc

Im a bit confused why you only need it for 400ms but. To get that output you're going to draw around 53A out of your SLA (assuming around 75% efficiency) So you're gunna need a decent size SLA. There are many ways to build want you need.

• 48 volt to 12 volt DC-DC reducers 200 watt, suitable for golf cart, telecom, and automobile electronics.
• The FP-DCC1 outputs are regulated to provide 24 Vdc for input voltages normally encountered in 12 Vdc battery circuits. If voltage in excess of 15 Vdc (possible.

One way you could do it is to build a DC-DC switchmode stepup using a toroid transformer. You can buy the toroid core and wind it yourself quite easily, and you learn alot from doing so. Just keep in mind it cant be any type, has to be a core intended for a switchmode powersupply. (faulty/damaged highpower car amps normally have some toroid cores you can reuse.) Youll have to play around trying different numbers of turns to work out which is the best.

Sep 15, 2014  pls, i need to convert 48 volts DC to 12 or 24 DC, Originally posted by Gadget@Mar 8 2006, 09:02 PM Some major problems using an LM7812. The 1st is that the Maximum specified input voltage is 35 volts for a LM7812, and 40volts for the 7824 (24 volt version) so you would need a Pre-regulator, or some method to drop the input.

If using the toroid core from a car amp you can see how many turns they used on the primary. It will probably be a something like 10 turns with a tap.

Center tap the primary and feed +12V into the tap, then ground each side of the primary through a fet. You can then drive each of the fets through a transistor in a push/pull arrangement from any of the wide range of swtichmode controllers available.

The TL494 controller is one i've used before that maybe suitable. Centertap the secondary winding and add two high current schottky diodes + a large cap. (You want to use a center tapped secondary because it means you only need two diodes to create a fullwave rectifier.

Without the centertap you'd need 4 diodes for fullwave and that eats into the efficiency of the design.) Dont forget to matchup/tune the switching frequency to get the best efficiency from the toroid you're using. That part is critical if you wind your own transformer, as you dont really know its exact characteristics.

Start at low current and setup multimeters to watch input/output current/voltage and map out the efficiency over a range of switching frequencys. (Dave's video on switchmode design shows this i think) I've used this method to build a nice voltage stabiliser (10-15V input - 12V 10A output) I've even managed to drive this kind of circuit from a 555 timer + inverter logic gate to generate the push/pull output. There are lots of extra features you can add too, like a high side current sensor IC and feed that back into the switching controllers error amplifer so you have a current limit.

If i remember ill post a circuit diagram tomorrow. I have to be more specific 1. I read the data sheet and I know that it's says there it can work on output with maximum 1.5A. But I also know that if you use right voltage, current, peak current on external components (mosfet, inductor, diode) u can theoretically (use formula) get infinite voltage and current. But practically, after a limit u will not find any external components with those characteristics.

Another problem is that the energy loss (efficiency More. More power on input and more heat. This and all StepUp controllers are actually a timer for switching, a comparator to regulate voltage and a short circuit/temperature protection, all put together in the same IC.

I want this solution to be a custom design so that I can integrate it in a PCB. I want to find all the components(the inductor might be a problem) used for this solution on the market, not to be custom made.

12 Volt Dc Motors

What I need can be started 1 minute before this single big spike (aprox 400 ms up to 10A - theoretically I need 12 spikes at 8A for 15ms with 5ms in between, meaning a total time of 180ms). During this spike voltage and current can drop(at the end of the spike it can be 36V and 5A). I know I can use more and bigger capacitors but it's not my preferred solution. I want to use maxim 2, but preferred 1, at 4700uF/50V. If I buy mass products of this StepUp, they can offer me something expensive, regulated and with continuous voltage and current. On the one hand if I buy the variant at 3-5A, it does not behave well(short circuit protection come's up) at the spike I need.

On the other hand if I buy the variant at 8-9A with 10A spike, it is more expensive, bigger and with some features that are not useful to me. So, can some one come with a brilliant idea for what I need? Take a look at the LTC3721-1 Push-Pull Controller: Last Page of the pdf has a 12V to 48V reference design for you. Although you will probably have to beef up the MOSFETS used and the transformer core used in the ref.

How To Make 18 Volt Dc 12 Volt Dc

Design to handle a 10A burst @ 400ms. 90% efficiency rating. I would also recommend doing a google search for 'Push Pull Controller' to see if these are other options that suite your needs. For a Transformer core. I would go with either a P-core, PQ, or RM ferrite core to keep the PCB real-estate small. Toriods usually need a lot of board space and P,PQ,RM cores are much more easier to wind yourself. I doubt you will find a manufacture that provides an off the shelf 12-48V push pull transformer.

For a production you can provide specs to a transformer winder vendor to run you a set of a few hundred custom transformers that meet your needs.