My understanding is Ian is feeding the entire Buffalo Dac with 3.3V battery power; if you look closely for the input and output legs of the normal tridents, Ian just jumpered them with a simple cable. In order this to fly, they should be already at 3.3V.
If this is the case, that 1.3V trident will be using the battery power as well and no need for the 5V 2A line of the psu.
Would be great if Ian can confirm if this is the correct understanding though
To measure the internal resistance of a battery below 10m ohms, you need to use a precision resistor to compare. For below 10m ohm of batteries, there is no simple and cheap way to measure. The cheapest instrument and the special battery rack can be bought on taobao.
20A20V100W?????????????????????????-???
???????? ????10A?????26650 18650 AA AAA-???
The schematic is as follows
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You are right. However, Optimumnano may have omitted the test step. So to purchase Optimumnano's battery, you have to do test by yourself. In other words, it is best to double the quantity and compare enough to pick out the quantity.
It is best to leave them well and truly alone.
If they skipped the test step then they certainly have skipped something else...I would not use those cheap batteries even if they were given to me.
Lithium batteries are known to catch fire, so if I put some in my house it is at least going to be a brand with some sort of quality control and runs on the board.
If they skipped the test step then they certainly have skipped something else...I would not use those cheap batteries even if they were given to me.
Lithium batteries are known to catch fire, so if I put some in my house it is at least going to be a brand with some sort of quality control and runs on the board.
"LiFePO4 is one of the safest of the Li-Ion battery formats，it is as safe or safer than lead acid"
YouTube
LiFePO4 Batteries On Boats – Marine How To
Assembling a Lithium Iron Phosphate Marine House Bank | | Nordkyn Design
YouTube
LiFePO4 Batteries On Boats – Marine How To
Assembling a Lithium Iron Phosphate Marine House Bank | | Nordkyn Design
example diagram
The internal resistance of Optimumnano's batteries is mostly below 10m ohms, but some of them is poor quality. As the photo, Optimumnano's battery is measured 9m ohms, but considering that the measuring instrument is still relatively cheap, there may actually be 5.5~6.5m ohms.
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I see what you mean, thanks a lot !!! This is actually a BIIISE, which is great as this is more or less the latest board generation...I did not find a schematic, but I trust Ian has measured the routing on those boards to figure he can simply feed the whole board with 3.3-3.4 V instead of feeding each reg input with its own 3.3V supply...which maybe is advisable to separate analog and digital, no ? Channel separation on the source would be as well not bad...so in the end you want Three 3.3V connections for a BIII I guess:
- One for connecting the main power input which feeds DVCC, VDD_XO via jumper cable and VDD reg for 1.2V (255mA)
- One for AVCCL 100mA (if dual mono I would combine ACCCL and AVCCR), so optional:
- One for AVCCR 100mA
- Maybe - for discussion - one for VDD_XO separately
mA is for the 9038 version.
For my current Dual Mono 9018, this would translate to
- Two main
- Two ACVCC
- Two VDD_XO
Plus the power for the FifoII and DualXO with OXCO/Pulsar plus WaveIO
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Yes, I agree. I would also expect this level of seperation/isolation would help to improve performance.
Btw, extending this principle to the output stage, if one goes for seperated supply lines for Mercury for left and right channels (doable with 2 LifePO4 boards/total of 4 13.3V lines), it becomes as close as it gets to dual mono setup (both seperated AVCC as you mentioned, and output stage becoming separated from each other)
Its a long time that I installed my FifoII with Dual clocks..no reason to touch it, so I just looked into the manual:
The FIFO wants 5V... maybe Ian can comment how to get the 3.3V into the FiFoII...for the Dual XO we need another separate 3.3V instead of a reg, that is clear.
The WaveIO wants 5V with at least 0.5A plus a 3.3V for the isolator....
The FIFO wants 5V... maybe Ian can comment how to get the 3.3V into the FiFoII...for the Dual XO we need another separate 3.3V instead of a reg, that is clear.
The WaveIO wants 5V with at least 0.5A plus a 3.3V for the isolator....
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I also have a McFIFO and McDualXO (not operational, sitting in a box so far
)I am planning to feed regulators in the McDualXO from 3.3V battery lines as you mentioned, I would be interested if there is a way to run McFIFO also from battery lines as well. (I was planning to use the regulated 5V power supply in the Lifepo4)
Hi Ian
Apologies if this has been discussed before but will the Lifepo4 supply be able to calculate how much current is being drawn (at each of its outputs) and be able to roughly calculate the remaining battery life in minutes (showing both of the above on the display)?
Also, I don't know how fast a lifepo4 battery will drop to dangerously low voltage levels as it becomes discharged but Is it possible to have some sort of warning that this will be about to happen and alert the user by say a flashing screen or even an audible warning?
Thanks
Apologies if this has been discussed before but will the Lifepo4 supply be able to calculate how much current is being drawn (at each of its outputs) and be able to roughly calculate the remaining battery life in minutes (showing both of the above on the display)?
Also, I don't know how fast a lifepo4 battery will drop to dangerously low voltage levels as it becomes discharged but Is it possible to have some sort of warning that this will be about to happen and alert the user by say a flashing screen or even an audible warning?
Thanks
Well...the regulated 5V line looks to me really like an emergency exit...I would like to try to avoid it as it is not battery fed, but fed by the switching power supply/ wall plug intended for battery charging service. This is dirty.
Currently I use an own shunt reg (placidhd) for the Fifo. I am considering to give those reg a choke input supply as well and some hexfred diodes...but battery supply is a better option I guess...but the 5V from a wall plug switching supply is a nono for me.
Currently I use an own shunt reg (placidhd) for the Fifo. I am considering to give those reg a choke input supply as well and some hexfred diodes...but battery supply is a better option I guess...but the 5V from a wall plug switching supply is a nono for me.
FiFoII should be unable to use LiFePO4 as a power supply, because the LDO on FiFoII is difficult to pass by. The McFIFO LDO has a way to by pass. Even if the ultra capacitor power supply can provide 5V, it will reduce the effect because of the LDO on the FiFoII. The conclusion is that FiFoII should be eliminated, replaced with McFIFO or the coming FIFO for pi raspberry.
Yes, that's correct.
LifePO4 doesn't have 1.3V rail, so it has to be regulated from 3.3V battery rail. All other sections use 3.3V rails. So, I removed all LDOs to keep the quality of battery power.
If you can, the best way is to power each 3.3V load with independent battery rails. Please let me know how much in difference from powering them all with one battery rail.
Regards,
Ian
Regards,
Ian
My Fifo is safe to be fed with 3.3V rather than 5V without problem. On board LDO will be bypassed automatically if the drop voltage is less than 0.3V.
For clock board, is also OK, but to reach best possible sound quality, I would suggest remove or bypass on board LDOs if you feed it with 3.3V battery rails.
Regards,
Ian
My LifePO4 power supply is designed with over discharge protection. If the output voltage lower than 3.0V, it will be turned off and back to charge automatically to protect battery from damage. For normal DAC applications with A123 26650 cells, this usually takes more than 12 hours, so no worry.
It also equipped with a timer for battery double safety.
Regards,
Ian
On My LifePO4 board, the 5V linear output was designed for powering digital sections before isolator, such as RPi or streamer. Though it's an 2A LT3042 ultra low noise regulator, but it's still far from battery power, and it's also non-isolated. If you are really worry about it, you can turn it off 100% by disabling it from the OLED manual. This is another feature of the on-board controller.
Regards,
Ian
Thanks a lot, great to hear that I do not have to change your fifoII for the MCfifo...(...or is the MCFIFo much bezter ? I only listen to PCM in stereo up to 192k).
Yes, that was my understanding, the 5V/2A is for dirty stuff like digital front ends...and I guess if you want that part to sound really nice, you actually have simply to build a properly filtered raw-DC supply, ideally with some double bobbin transformers (cheap from hammond), hexfreds, chokes and nice silmics...and than the 5V rail is highend as well....
Yes, that was my understanding, the 5V/2A is for dirty stuff like digital front ends...and I guess if you want that part to sound really nice, you actually have simply to build a properly filtered raw-DC supply, ideally with some double bobbin transformers (cheap from hammond), hexfreds, chokes and nice silmics...and than the 5V rail is highend as well....
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