Voltage Drop Issue with Bluetooth Audio Module Using 3.7V Li-Ion Battery Message

LeonSKenn

Aug 10, 2024
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Hi everyone,

I’m working on a project involving the Bluetooth audio module powered by a 3.7V 3200mAh Li-ion battery. While the module technically supports a voltage range of 3.7V to 5V, I’ve encountered a significant issue when the battery voltage drops below 4V. As the voltage decreases, the audio quality from the BT module deteriorates dramatically, resulting in noticeable distortion and hissing sounds.

Here’s what I’ve tried so far:

Direct 5V Power Supply: When I directly power the BT with a stable 5V source, the audio quality is excellent. This leads me to believe that the issue is indeed related to the lower voltage from the battery as it discharges.

Ordered XL6009 for increase the voltage but it is not worked as we want.
First i wired it direct and there is too much noise in sound , then added a capacitor (25v 2200uF) less noise but still there.


I need a reliable solution to ensure a constant 5V output from my 3.7V Li-ion battery to maintain good audio quality.

Any advice or recommendations for a more effective power management solution would be greatly appreciated. Thanks in advance!
 

Bluejets

Oct 5, 2014
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Bluetooth audio module
You may know what you have in front of you but others here would have zero idea.
supply details and circuit diagram. (NOT fritzing)
Note that any switching regulator will be noisy requiring (at least) best practices noise isolation.
 

Delta Prime

Jul 29, 2020
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Ordered XL6009 for increase the voltage but it is not worked as we want
Input voltage XL6009 Buck/Boost converter is 5Vdc to 32Vdc.
The output voltage is variable.
You are supplying one 3.7Vdc(nominal) 4.2Vdc (maximum) Li-ion (Cell) not battery, to a component that requires a (Minimum) 5Vdc input & was never intended for your application.
You need a fixed 5Vdc output DC to DC Boost converter that requires as low as 2Vdc as input.
Readily available 5Vdc boost converter fixed output "Modules" online.
 
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Martaine2005

May 12, 2015
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I need a reliable solution to ensure a constant 5V output from my 3.7V Li-ion battery to maintain good audio quality.
Well, I’m sure that you know this is impossible.
Battery voltage drops therefore electronic items no longer work!..
A constant voltage is only possible from a reliable mains voltage source or of course a battery for a limited amount of time.
A boost converter will drop out quicker if supply is via a battery.
 

LeonSKenn

Aug 10, 2024
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Well, I’m sure that you know this is impossible.
Battery voltage drops therefore electronic items no longer work!..
A constant voltage is only possible from a reliable mains voltage source or of course a battery for a limited amount of time.
A boost converter will drop out quicker if supply is via a battery.
Yes ,you’re right. No booster just battery actually main problem is sound quality ,are there any trick anybody knows about sound quality how can i increase the quality of sound i am using bt-201.
 

Martaine2005

May 12, 2015
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We don’t know the speakers, amp or any flashing lights you have on a poor 3.7v battery!!
Give all the information.
 

73's de Edd

Aug 21, 2015
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Sir LeonSKenn . . . . .

If you don't have any critical weight / size limitations, my solution would be to use three of those 3.7V 3200mAh Li-ion cells , connected in series and then feed into a low voltage drop 5V three terminal linear regulator with minimal filtering.
Result is no RFI + a rock steady +5VDC output until those cells are finally pulled down to their safe use +2.5 each lower thresholds.
That is still being less than your <+5 . . . . . .where audio problems start insetting!
Don't think of enhanced audio, such as a compressor, as I see the distortion aspect as completely being the criticality fault of supply voltage threshold.
If thinking of the buck converter, be wary of its DC output purity on possibly modulating the audio.
I use that modification circuitry on some of my LED flashlights, to keep them at a PEAK and UNIFORMLY EVEN brightness until that eventual end voltage level threshold drop...

73's de Edd . . . . .

A nice thing about being senile, is that you can hide stuff REALLY GOOD !

TEST

1 . . . 2 . . .3 . . . .TESTING . . . .to see what an" inline spoiler" option is . . . . .'shudda-woulda-coulda called it a BLUR-ER-ER-RER . . . .
 
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