Powerboost 500 Basic output not 5V

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javen
 
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Powerboost 500 Basic output not 5V

Post by javen »

I recently bought 2 Powerboost 500 Basics and have tried to use one to power a small strip of Neopixel LEDs. I noticed the brightness was not the usual intensity. I measured the output voltage at 4.02V. I disconnected the LED strip and measured the open circuit voltage across the 5V and GND pins at 4V. I then pulled out the other Powerboost I ordered with no modifications and and measured 4V on the output open circuit. In all scenarios I have used a 1 cell Lipo and used 3 different lipos and confirmed they were charged and outputing greater then 3.9V. Does anyone have any thoughts on what is wrong?

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adafruit_support_rick
 
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Re: Powerboost 500 Basic output not 5V

Post by adafruit_support_rick »

It's odd that you would have two of these doing exactly the same thing. Are you sure your meter is accurate? Check it against a known 5V source.

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adafruit2
 
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Re: Powerboost 500 Basic output not 5V

Post by adafruit2 »

disconnect everything. Then plug just the lipo in, look for the green LED, check the output voltage - what is it?

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javen
 
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Re: Powerboost 500 Basic output not 5V

Post by javen »

Voltage across %V and GND pins
Voltage across %V and GND pins
Output Voltage.jpg (853.68 KiB) Viewed 292 times
@Rick I just tested my meter with the 5V and 3.3V lines on 2 Arduino Unos and got 4.9V and 3.3V respectively. It doesn't look like my meter is inaccurate.

@Adafruit2 I disconnected everything from both Powerboost boards and connected only the battery. Battery voltage at the terminal is 4.2V and the output across the 5V and GND pins on the Powerboost is 4.2V or lower. This is for both boards. One of the boards is straight out of the bag never connected to anything.

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adafruit2
 
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Re: Powerboost 500 Basic output not 5V

Post by adafruit2 »

can you take a picture straight down? we can't see the actual board! thx :)

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javen
 
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Re: Powerboost 500 Basic output not 5V

Post by javen »

Board.jpg
Board.jpg (768.09 KiB) Viewed 289 times
Yes, here you go! Thanks for the quick responses.

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adafruit2
 
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Re: Powerboost 500 Basic output not 5V

Post by adafruit2 »

everything *looks* right - and we test these before shipping to verify the output is 5V.
i guess we can replace it... this is the first we've heard of that kind of issue- email support@adafruit for a replacement!

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javen
 
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Re: Powerboost 500 Basic output not 5V

Post by javen »

Would you like me to ship the two modules back to you? Maybe you could confirm the problem and verify the cause. If I'm not making a mistake, it might reveal a bad batch and you could troubleshoot the problem.

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adafruit2
 
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Re: Powerboost 500 Basic output not 5V

Post by adafruit2 »

Sure, when you ask for replacements, request a return envelope and have it be ATTN: PHIL

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