If a power supply is not connected to the USB and 5V terminals, is it possible to connect a 3V (1.5V x 2) dry cell battery to the Li-Po terminal and use it?
one problem is low voltage brown out… the AAA batteries dont hold the required voltage like the Lythium do
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Would lithium AAA also brown out?
Hi there,
So I would do something like this if it were me.
they sell just the boost regulator small board 1.8 to 5v adjustable output too.
I would grab a two cell holder if that’s what you want and hot glue the tiny pcb Booster to 3.3v the bottom like they do.
HTH
GL
PJ 
Would adafruit 1A 5v booster work just fine for 2 AAA?
Hi there,
So,The ESP32-C3 chip works with a voltage range of 3.0–3.6 V. The recommended voltage for a single power supply is 3.3 V, with an output current of at least 500 mA.
just follow the data sheet.
GL pj
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you cant make power where it does not exist… this is a simple power calculation… boost or buck converters are just transormers… they can only convert voltage to current or vice versa… but cannot create power
Some important safety questions, I am pretty new with microcontrollers, so I use them as recommended out of the box:
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After taking a closer look at the XIAO models available, there’s a warning about adding any batteries with USB-C at the same time for RP2040 chips. I hadn’t expected this. I have the sense model which does use LIPO 3.7v rechargeable batteries. But it also recharges. Likewise like the ESP32C3, it does do a LIPO recharge.
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Could automatic recharge cause conflict with using a simple alkaline AAA/AA battery adapted case or does the buck booster prevent feedback to the batteries if you plug in the USB-C while having dry cells attached? What are the risks compared to using something like the RP2040 model? Is recharge automatic?
as a rule… you dont want to use AAA/AA batteries… for simple facts… they do not power these devices… this is the reason the 3.7 v LiPo was developed… you can say yeah well but i still want to do it… well i also want to have sex with a woman tonight but it ant going to happen… and spending money or time trying to make it happen is a waste
Hi JS-Drone,
Your post is too vague to ask important questions about safety.
At the very least, you need to post the model number or link to the part you are using and a connection diagram showing the pin names.
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Here’s what I got, can we make it use just 3xAAA alkaline batteries or 3xAA using a RP2040NP Xiao?
From what I read, it isn’t safe to use both dry batteries or rechargeable LIPO on this with the USB-C
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XIAO RPN2040
(search keyword “battery”) -
LED 12 Bit
24 Gauge Wire connections -
battery spring 5 No. positive and negative contact pieces 11 * 13MM which I am building with a 3D printer
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100w Type C USB
This is everything you should need to know. My thoughts are with the XIAO RPN2040 you just have to lockout the USBC permanently with glue maybe or a 3D printed plug to keep it from being tampered with or inaccessible and solder the battery terminal leads to it for it to work. It doesn’t clearly say that there is a risk for batteries by themselves.
There is no problem to connect a non-charging battery to the VIN and GND pads on the back side of the board, provided that the XIAO_RP2040(without charging capability) is used and is not powered from USB-C.
You would still need a buck booster from on the VIN/GND from 3.5 to 5v to keep the voltage stable I would assume as we lock out the C port.
Are you looking at the schematic?
The VIN pad is connected to an RS3236-3.3 LDO that allows input voltage up to 7.5V.
What is the voltage of the battery you are using?
1.5 v AA or AAA ea, and considering using just 2 or 3 depending on the LED at the end. From the prior replies it says that you need a steady power supply, that the voltage is too inconsistent using dry cell batteries to a XIAO. From what I understand, the XIAO should be able to control the voltage going out, but the other posts suggest intermediate steps, perhaps adding a resistor for the LED too. But just focusing on the input voltage, is it consistent enough to use as is without a buck booster?
Have you looked at the schematic?
This thread is originally about the XIAO_ESP32C3, which has high current consumption and is not suitable for use with AA or AAA non-rechargeable batteries. You should have originally posted a separate topic about XIAO_RP2040.
As far as XIAO_RP2040 is concerned, there is no need to step down the voltage as long as it is below 7.5V.
How do I connect the LEDs?
I am would be stepping the voltage up from 3v to 5v for steady input. I am apologize about the thread but it is still relevant to adapting AAAs as power input to microcontrollers, isn’t it? But it is a different type of XIAO, I am sure others will need to learn that too, that they work much differently than the others in the series.
I am still figuring out the LED schematic, I am going to use an arduino schematic plan, basically 3 leads in, VIN/GND and D1.
The “HIGH” output of XIAO is 3.3V, so it is better to connect the LED power supply to 3.3V.
Oh, so it wont do 5V like the ESP32C3 out? I see it says SV and 5V there on the RP2040. What is SV? I am still learning about their design.
The XIAO series port voltages are,
HIGH=3.3V
LOW=0V
@JS-Drone
so it wont do 5V like the ESP32C3 out? I see it says SV and 5V there on the RP2040. What is SV?
Where is it written?