How to power Power Supply Regulator

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
Yes, transformers are always AC.

I'm not so sure that the regulator you have in mind is all that well designed...

If the absolute maximum DC voltage allowable for the IC is 20 vdc then that means you must not apply more than about 14 VAC.

The DC voltage you get after rectifying the AC from the transformer is Vac * 1.414.

For eg a 12 Vac transformer will produce around 17 volts DC. A 15 Vac transformer will produce around 21 volts DC and so on.

So a 12 volt transformer is about as high as it is safe to go for the IC used. This is because you need to account for higher than expected mains voltages (that increase the output of the transformer) and also light loading of the transformer.

In my opinion the product is not well thought out seeing as it is stated as being suitable for providing up to 15 volts DC output. The board is also a dual supply (-and + output) and so the transformer needs to have two identical windings of 0-12 and 0-12 Vac.
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
It states you need the following,

1)The AK4490 PCB can work immediately with only I2S signal and power supply connected, one 3.3V (>300mA), one 5.0V (>100mA) and one +-12V (>100mA) regulated power supply in the default parallel operation mode.

So that is a power supply with four rails, +3.3, +5 and a dual -/+12 volt.

I don't know what to recommend for you as a kit or ready built. Its easy enough to build your own though, and power it all from a single 12-0-12 or 15-0-15 transformer.

Why not ask the seller what PSU they recommend.
 

otec

Member
2016-02-04 1:01 pm
It states you need the following,

1)The AK4490 PCB can work immediately with only I2S signal and power supply connected, one 3.3V (>300mA), one 5.0V (>100mA) and one +-12V (>100mA) regulated power supply in the default parallel operation mode.

So that is a power supply with four rails, +3.3, +5 and a dual -/+12 volt.

I don't know what to recommend for you as a kit or ready built. Its easy enough to build your own though, and power it all from a single 12-0-12 or 15-0-15 transformer.

Why not ask the seller what PSU they recommend.
So these will be 2 transformers that convert AC to DC right? How can a single transformer do both 3.3V and 5.0V at the same time?

Sent from my Nexus 6P using Tapatalk
 

wintermute

Administrator
Paid Member
2003-08-03 11:43 am
Sydney
The transformers do not convert AC to DC you need a rectifier to do that. A transformer just changes from one AC voltage to another (or in the case of an isolation transformer the output voltage is the same as the input voltage, but the two voltages are isolated from each other).

You can have two separate secondary windings on a single transformer which give you different output voltages.

For a better understanding of transformers I'd recommend having a read here http://sound.westhost.com/xfmr.htm

Tony.