2 x regulators for double current?

[qweets]

hello everyone : )

i have an old PSU for a HP printer that can output approx 18v @1.1amps
(which i believe is 19.8 watt)

My circuit however needs aprox 10v @1.5amps ( 15 watt)

I have two 10v regulators that offer 10v @ 1amp

So I wonder, can I use these 2 x regulators together in parallel with my PSU to provide my circuit with enough current?


thanks for any help. : )

 

[Resqueline]

The regulators themselves might be parallelled to get the required current, but here the PSU is the limiting factor with its 1.1A capacity.
Only by using a switchmode regulator off the PSU can you keep the wattage and get the neccessary higher current. It also needs to have a higher than 75% efficiency.

 

[qweets]

thanks for your reply : )

the regulators are "Linear voltage regulator,BA17810T 10V 1A" , i do not think they are switching type.?

i also have a PSU from an old PC ...i think it may be around 300watt with 12v

but i've just read the 10v regs need 12.5v minimum too work. ....typical. : /

hmm..not sure what to do now? I might look on ebay for a higher current psu? As i cant see a switching type regulator that will fit my bread & vero boards. not sure how that would work?

 

[qweets]

i just found a regulator that can output 2amps , so hopefully i'll be o.k with that and the 18v 1.1amp psu. fingers crossed. : )

thanks for your help. : P

 

[(*steve*)]

You understand that unless it's a switchmode regulator that 2 amps out requires 2 amps in (actually a little more).

 

[qweets]

hi : )

i did not need the full 2amps, but yes i think i need to just buy a new ac/dc adaptor with a higher amp output.

I was told that I can up the amps in a step down conversion under certain situations.
So seems i need to disregard that in this instance.: /

thanks for your help : )

 

[davenn]

hi : )

I was told that I can up the amps in a step down conversion under certain situations.
So seems i need to disregard that in this instance.: /

thanks for your help : )

yes but the original PSU transformer still has to be able to supply the current you want
and the indication is that it cant.

D

 

[qweets]

thanks.: )

i just noticed a 10v 20 amp psu for sale. i wonder, would this have a standard 13 amp fuse in the plug? or a special fuse to provide the 20amps?

 

[(*steve*)]

I assume you're in the UK

That would have a mains fuse rated at around 2A as a guess.

I have no idea if/how the power supply might limit the output current.

 

[qweets]

yep, uk : )

So that would be 240v 2a converted to 10v 20a

Stepped down voltage, but the amps raised,

This is why i thought a 18v 1.1a psu might go to 10v 1.5a .

not to worry i have a psu that i may buy, should do the trick.

peace: )

 

[(*steve*)]

The power supply you are talking about is either switchmode or has a transformer. Both devices can reduce voltage and increase current.

You are talking about a linear regulator which reduces the voltage but the current remains constant.

That's one reason why we use transformers to reduce the voltage before using a linear regulator to regulate the output voltage.