Step up converter not producing enough voltage

Hello,

I bought a step up converter on Amazon. It basically has the usual three pins, Vin, Vout and gnd. Vin is any voltage < 5V and Vout is supposed to be 5V.

I'm connecting a lipo battery to it, when I measure just the battery, I get the expected 3.7V. When I connect the battery to Vin, I get this:

Vin - gnd = 0.2V
Vout - gnd = 2.1V

I'd have expected to see:
Vin - gnd = 3.7V
Vout - gnd = 5.0V

I purchased 10 of these and I tried a couple, they all behave the same. Any ideas?

Thanks.

Here is the particular model:

Hi,
What size is your Lipo battery?
Can you please post a picture of your setup, so we can see your component layout.

Thanks.. Tom.. :smiley: :+1: :coffee: :australia:

Looks like you battery can’t supply enough current. Try a couple of AA batteries just as a test.

As a general note this sort of step up converters are very poor, especially if you are trying to draw a moderate amount of current from them.

Hi,

Specification:
Condition: 100% Brand New
Model: T64
Input Voltage: 0.9-5V
Output Voltage: 5V
Input Current(max.): 480mA
Start Voltage: 0.8V, Output Current: 7MA
Input Voltage: 1-1.5V, Output Voltage: 5V, Output Current: 40-100MA
Input Voltage: 1.5-2V, Output Voltage: 5V, Output Current: 100-150MA
Input Voltage: 2-3V, Output Voltage: 5V, Output Current: 150-380MA
Input Voltage: >3V, Output Voltage: 5V, Output Current: 380-480MA
Work Frequency: 150KHZ
Conversion Efficiency: 85%
Weight: Approx. 13g / 0.5oz
Size: Approx. 11 * 10.5 * 7.5mm / 0.4 * 0.4 * 0.3in

Tom... :smiley: :+1: :coffee: :australia:

Wow 7 Mega Amps out for just 480 millie amps in. Either some one has created energy out of nothing, or nothing is what the seller of this product knows about electronics.

1 Like

I basically just connected my battery to the converter for testing on a bread board, just to see if it produces the expected result. It's just the battery and the converter, it is not connected to anything else. The lipo is 150mAh.

What has that got to do with your question?

You have been given advice but are choosing to ignore it. Why ask the question in the first place if you just ignore the answer.

You either have a battery that won’t supply the current or you have a crap boost converter.

The mAh rating of your battery has nothing to do with the current it can supply. It is no supprise it can’t supply nearly half an amp.

@Grumpy_Mike , I am not ignoring the advice given, @TomGeorge asked what battery I am using and what my setup is so I was just answering his question. I do appreciate your input but please read the thread carefully before posting snarky comments.

Tom asked

To which you did not answer any of his two points. He asked about the size of your battery you just gave the mA hours rating which is not the size.

Well then, it's my bad.

What do you get using a 1.5V AA battery?

In addition to trying a different, known good source, also try a 1k resistor across the output of the converter. It's a bit of a long shot these days, but back in the old days you had these regulators that wouldn't power up well without a load.

How long did you leave it doing this condition? That’s a serious insult to the battery, try 3 or 4.5 from regular AAs as has been suggested.

You could also measure the current being drawn from the battery.

But with what you’ve told us, you got a bunch of bogus boosters.

a7

@missdrew Connecting a 1.5V AA gives me the expected result. Thanks everybody for your input.

I think perhaps the your li-po battery is dead.
So let's dispose and don't try to charge it.
(Except when you want to magic smoke.)

I'm surprized it can work (actually boost) from 0.2V. But clearly the cell is either dead or in protect mode (presumably from overcurrent?) Perhaps its oscillating between periods of working and periods of protect mode - that would explain the output voltage being that high, and the 0.2V on the input is a time average.