Hello all
I'm going to buy the iFi Zen DAC very soon....it relies on 5V USB port for power
How would you design a hifi grade 5V / 3A linear power supply?
Thanks
I'm going to buy the iFi Zen DAC very soon....it relies on 5V USB port for power
How would you design a hifi grade 5V / 3A linear power supply?
Thanks
> 5V / 3A
The power seems to be 1.5W, not 15W. ZEN DAC by iFi audio | Super-affordable DAC/amp from iFi audio
At 5V 3A, it is a significant design problem.
At 5V 0.3A, I would look at a USB Charger (switcher) and one of Mark Johnson's DC filters which people seem to rave about.
The power seems to be 1.5W, not 15W. ZEN DAC by iFi audio | Super-affordable DAC/amp from iFi audio
At 5V 3A, it is a significant design problem.
At 5V 0.3A, I would look at a USB Charger (switcher) and one of Mark Johnson's DC filters which people seem to rave about.
The digital signal will come to the unit from a phone or tablet thru an OTG cable...Can a phone or tablet provide the 0.3A required?
The specs doesn't say what should be the amp needed for the 5V jack on the rear panel....
Assuming I want a linear power supply that provide let's say 5V @ 1.5A, would you have any recommendation?
The specs doesn't say what should be the amp needed for the 5V jack on the rear panel....
Assuming I want a linear power supply that provide let's say 5V @ 1.5A, would you have any recommendation?
At such low power (less than 0.5A) the perfect application for a linear LDO PSU and not a switcher. Certainly for a DAC an LPS is the better solution. Any switcher will need work to make it quiet and the linear will be quiet without added circuitry. Even an output filter that works OK (a band aid really) will not prevent the switcher from polluting mains voltage nor does it prevent stray RF. Switchers are not quiet by design so a good ultra low noise linear has an advantage by design. TPS7A4700 or LT3045 based designs will be good.
I like this one which can be used with a 6V transformer of good quality (choose 2x the required VA rating):
TPS7A4700 Ultralow-noise (4mVrms) Power Supply 1.4-20.5V,1A for Audio DAC | eBay
Added bonus is when you can build the PSU with a real on/off switch instead of relying on cheap, often not so reliable SMPS that stay powered on even when you are not at home.
I like this one which can be used with a 6V transformer of good quality (choose 2x the required VA rating):
TPS7A4700 Ultralow-noise (4mVrms) Power Supply 1.4-20.5V,1A for Audio DAC | eBay
Added bonus is when you can build the PSU with a real on/off switch instead of relying on cheap, often not so reliable SMPS that stay powered on even when you are not at home.
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Does it already come with the rectifier?
I mean it's just a question of attaching a transformer? Is there more detailed instructions somewhere?
When you say good quality transformer, would you have some links as recommendations?
Thansk
I mean it's just a question of attaching a transformer? Is there more detailed instructions somewhere?
When you say good quality transformer, would you have some links as recommendations?
Thansk
Yes, you can easily build a separate linear power supply. The issue is that the cost to do so might be equal to half the cost of the Zen dac. You will need a transformer, diodes for rectification, capacitors for smoothing out the current and resistors to get the proper voltage (or a voltage regulator) correct. Then you will need a case to hold it, a power switch and an outlet for a power wire to connect the 5V power input of the dac. Or you can purchase something like this: HIFI 25W DC5V linear Power supply with display for USB DAC / Raspberry Pi PSU | eBay
You could certainly use the eBay unit referenced above. It has rectification, which you can observe in one of the photos, where D1, D2, D3 and D4 are visible. Those are the diodes for the rectification. For this unit to function as a LPS you would need to purchase a transformer. This type of transformer would work: 15VA TALEMA Toroidal Transformer Potted For DAC Headphone Pre-Amplifier,115/230V | eBay