Hmmm at hte moment is none of these in Ebay, only these ones : Ultra Low Noise HiFi Power Supply TPS7A4700 DIY Preamplfier DAC Raspberry Pi PSU | eBay
You have some pcbs ?
You have some pcbs ?
Don't forget about the dropout/clipping voltage that each half of the bridged LM4780 is gonna eat. I'd say +/- 28 volts would be more on track for your 4 Ω load; more like +/- 35 volts for an 8 Ω load.
It really depends how much devices you are planning to plug into Rpi. If you plan to keep Rpi using under 1A then go for TPS7A4700, it has so much better resolution than LM or LT linear regulators.
Best Regards,
Aleš
bridged lm4780
i would say that if you have 4-6 ohms speakers you should not feed your bridged lm4780 with more than + - 20volts.
if your speakers are 8 ohms or more , 26-28volts would be great, but NOT over 30volts . Never!
i would say that if you have 4-6 ohms speakers you should not feed your bridged lm4780 with more than + - 20volts.
if your speakers are 8 ohms or more , 26-28volts would be great, but NOT over 30volts . Never!
??? Explain your reasoning for that, sir. I see nothing on the data sheet that demands that restriction.
I am curious as to why there are TWO series-connected LEDs in the adjustment leg portion of the circuit. ????
if you bridged two lm3886 and you use 4-6 ohms speakers , each lm3886 will see the speaker impedance as half as your total impedance , in this case 2-3 ohms.
You cannot have more than +-22volts , check Texas instruments web page.
if you use 8ohms or more , same rule, each lm 3886 will see 4 or more ohms, for 4 ohms lm 3886 will be happy with less than +-28 volts.
lm 3886 is half of the lm4780, so there should be the same rules , even more drastic.
if you want to apply more than +-28volts you should have either very good active cooling , either more than 8ohms impedance speakers....
Again this is when you want to have 2 lm3886 bridged , or the two halves of the lm4780 bridged.
You cannot have more than +-22volts , check Texas instruments web page.
if you use 8ohms or more , same rule, each lm 3886 will see 4 or more ohms, for 4 ohms lm 3886 will be happy with less than +-28 volts.
lm 3886 is half of the lm4780, so there should be the same rules , even more drastic.
if you want to apply more than +-28volts you should have either very good active cooling , either more than 8ohms impedance speakers....
Again this is when you want to have 2 lm3886 bridged , or the two halves of the lm4780 bridged.
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" using a bridged configuration, Vcc would have to be equal to ±20V to keep the IC's power
dissipation within 40W/IC when driving a 4Ω load! This equates to about 110W of output power in bridgedmode
driving a 4Ω load. When driving an 8Ω load, and using the same bridged pdmax equation and a
maximum of 40W/IC of power dissipation, the supply voltages would have to be ±28V. This equates to
about 120W of output power."
ti AN-1192 Overture™ Series High Power Solutions
page 6
dissipation within 40W/IC when driving a 4Ω load! This equates to about 110W of output power in bridgedmode
driving a 4Ω load. When driving an 8Ω load, and using the same bridged pdmax equation and a
maximum of 40W/IC of power dissipation, the supply voltages would have to be ±28V. This equates to
about 120W of output power."
ti AN-1192 Overture™ Series High Power Solutions
page 6
Bridged lm4780
Thanks gabe75 for explaining the voltage restrictions to dotneck335. I could not say it better.
Thanks gabe75 for explaining the voltage restrictions to dotneck335. I could not say it better.
Thanks Aleš for this great PSU PCB.
I have used for DAC and with minor mod, it can worked with fixed voltage regulator like LT1085-5.
Currently, I plan to use it for Pass ACA Class-A amp, which requires 19V/4.74A. For this implementation, is there any parts need to be upgraded for higher power ratings? Any comments is appreciated.
I have used for DAC and with minor mod, it can worked with fixed voltage regulator like LT1085-5.
Currently, I plan to use it for Pass ACA Class-A amp, which requires 19V/4.74A. For this implementation, is there any parts need to be upgraded for higher power ratings? Any comments is appreciated.
I meant no spamming or advertising.
I just wanted to build some LPSUs for my Raspberry Pi, Network switch, Router etc for music streaming purpose. My DAC has a teradak LPSU already so I will be needing 3 more regulator boards as of now.
After a bit search, I found these on eBay and ordered some.
LT1083CP Voltage Regulator 2mm PCB gold plated LM317 board Audio amp dac Hifi | eBay
I am planning to mount LT1083CP on these boards. Could you please let me know whether this will serve the purpose or not?
If I need to use +5v dc regulated output, should I use a 0-5V ac transformer or should I go for a 0-6v ac transformer?
I just wanted to build some LPSUs for my Raspberry Pi, Network switch, Router etc for music streaming purpose. My DAC has a teradak LPSU already so I will be needing 3 more regulator boards as of now.
After a bit search, I found these on eBay and ordered some.
LT1083CP Voltage Regulator 2mm PCB gold plated LM317 board Audio amp dac Hifi | eBay
I am planning to mount LT1083CP on these boards. Could you please let me know whether this will serve the purpose or not?
If I need to use +5v dc regulated output, should I use a 0-5V ac transformer or should I go for a 0-6v ac transformer?
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