There are some circuits of high colt dc-dc booster power supplies.
Input: 12v 16A (ATX power supply)
Requirement: Variable up to 48 or more

circuit 1
circuit 2
circuit 3
circuit 4

Note: In some circuits, transformer & bridge rectifier is used. Can I skip both parts and use12V, 16A DC from ATX as INPUT?

 

Build whichever one for which you already have the most parts available. Do bear in mind some parts may be obsolete or difficult to locate and not all designs on that site work straight off without a bit of trial and modification.

 

I found all these circuits refer to a TRANSFORMER, so they are NOT dc converters, just ordinary adjustable power supplies.

They will not boost the DC input value from the rectifier. Using a 12 volt dc source as input will limit you to 11 volts or so as a max.

 

None of those circuits are suitable, since they all require Vin>Vout. If you have 12V input and require 48V output, you need a Boost converter
AND if you want the the output voltage to go below the input, you need a Buck-Boost

 

High-volt dc-dc booster power supply, which is better

There are some circuits of high colt dc-dc booster power supplies.
Input: 12v 16A (ATX power supply)
Requirement: Variable up to 48 or more

circuit 1
circuit 2
circuit 3
circuit 4

Note: In some circuits, transformer & bridge rectifier is used. Can I skip both parts and use12V, 16A DC from ATX as INPUT?

You will please pardon a 'brace' of observations - to wit:

1) None of the attached circuits represent a 'boost' converter.
2) 48V ≠ 'high voltage'.

So...?

Please be advised that alacrity of response is quite often in direct proportion to appropriacy of title -- IOW inasmuch as you can't be bothered to put some effort into the framing of your question it's hardly a surprise that the membership fail to 'clamour' to your assistance!

With constructive intent
HP

 

So are you figuring if you ask the same question to the same people over and over you will get a different answer?

http://forum.allaboutcircuits.com/threads/12v-to-48v-power-supply-of-up-to-16a.128259/#post-1049550

 

Read this to get a basic understanding of the differences between the two types of supplies.

 

Circuit 4 for has R5 sufficient to open Q1 but since it's not a CC-source - i have doubts about the performance

Circuit 3 the Q3 (supposedly over current limiter) can pass negative voltage to the base of Q2 through BC NP junction ???

Circuit 2 -- not processed -- can't fast find L146 schematic -- otherwise seems ok by 1-st run

Circuit 1 -- no errors at 1-st pass

 

None of those circuits are suitable, since they all require Vin>Vout. If you have 12V input and require 48V output, you need a Boost converter

I searched "Boost Converter" and found following circuits:

Circuit 1, Can it generate output (48v 3-4A) with input (12v 16A)?
Circuit 2, Can it generate output (48v 3-4A) with input (12v 16A)?
Circuit 3, Can it generate output (48v 3-4A) with input (12v 16A)?

 

One of the biggest problem you will have with your concept is that ATX power supplies have very poor voltage regulation on their 12 volt outputs being their voltage regulation feedback reference points are based off the 5 volt and 3.3 volt output rails and the 12 volt rail is mostly just along for the ride.
Given that if you put a high current draw switching load on the 12 volt rail there is a good chance the ATX voltage regulation will be poor to outrightly unstable.

Which as with your other thread is why I recommend starting with a 48+ volt power supply and modifying its voltage control feedback circuit to be adjustable downward for your lower voltage needs rather than trying to run two SMPS based units back to back to step down from AC line voltages to 12 volts then back up to 48 volts.

 

Circuit 1, Can it generate output (48v 3-4A) with input (12v 16A)? http://www.linear.com/solutions/5727 < 3A ? maybe
Circuit 2, Can it generate output (48v 3-4A) with input (12v 16A)? 150W/48V !optimistic = 3A (design problems mentioned, but maybe)
Circuit 3, Can it generate output (48v 3-4A) with input (12v 16A)? NO Iout.max = 2.1A×12V/48V = 525mA

https://www.maximintegrated.com/en/products/power/switching-regulators/step-up-boost.html
Populate menus = ↓
_____IOUT 5A _____ ?
_VIN (max) 14.7 V
__VIN (min) 9.6V
VOUT (max) 48V

http://www.linear.com/parametric/Sw...!vout_48!iout_4.5!vout2_!iout2_!vout3_!iout3_

 

Please be advised that alacrity of response is quite often in direct proportion to appropriacy of title -- IOW inasmuch as you can't be bothered to put some effort into the framing of your question it's hardly a surprise that the membership fail to 'clamour' to your assistance!

Are we having a bad day, Hp?

 

There is 0-60V / 0-2A Variable Power Supply.

It will give 2A at 60V. Is it?
And it will give 10A at 12V or 5A at 24V. Is it?

Another one 0-50 /2A Variable Power Supply. Does it also give 2A at 50V and higher amp at lower volt?
Another one also.

Please confirm me, I want to build any of above circuit because their parts are easily available.

 

Hello,

No. A linear powersupply will not give more current than the transformer can deliver.

Bertus

 

No. A linear powersupply will not give more current than the transformer can deliver.

All three ones use transformer. Did you not check?

 

Hello,

If you want the powersupply to deliver 10Amps, you will need a transformer of at least 10 Amps.

Bertus

 

shall it be said that to get your supply specs matching your application specs
is
a
mission
impossible ...

e.g. it usually takes forever -- so we are at the very beginning with it here (this thread)

to make it quicker
the OP should set up tighter profile for what he want to get
and use some forehead -- get (20% to 200%) more powerful supply e.g 1.2W(switched) to 3W(linear) instead of actual 1W
or if the peak power demand occurs at irrelevant times e.g.
a startup / short periods / output quality don't care
you may to opt. your "power profile" there adding the +20% ... +200% to the RMS demand.

 

No. A linear powersupply will not give more current than the transformer can deliver.

So to get higher amp output, I should use transformer of higher amp output. Right.

Is it suitable to use transformer of higher amp output in above three circuit?

 

Hello,

To adapt the circuit for 10 Amps, you will need more output transistors (5 X) on a huge heatsink and a lower value (5 X) current sensing resistor.
Also the buffer capacitor should be 5 X larger.

Have a look at this design for a 30 Volts 10 Amps powersupply:
http://www.sentex.ca/~mec1995/circ/ps3010/ps3010a.html
http://www.sentex.ca/~mec1995/circ/ps3010/ps3010b.html
http://www.sentex.ca/~mec1995/circ/ps3010/ps3010c.html

Bertus

 

Hello,

If you want the powersupply to deliver 10Amps, you will need a transformer of at least 10 Amps.

Bertus

Unless he (the TS) wishes to implement an 'impulse generator' (e.g. a photo-flash unit, cardiac defibrillator, certain 'spot welders', etc...) wherein a reactor (usually a capacitor) is 'protractively charged' for abrupt, intense discharge 'pulses' -- Though, based upon his posts, I see no reason to assume as much? @crazybuoy please describe your intended application such that we may better assist you

Best regards
HP