Questions tagged [charger]

A device which controls the voltage and current being delivered to a capacitor or battery.

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74 votes
3 answers
102k views

What is the ideal way to handle data pins D+ and D- on a USB power adapter to be compatible with fast charging on devices?

I have found that many USB wall chargers use a resistive voltage divider to set the D+ and D- pins to a specific voltage, usually between 2 and 3 volts. Other USB wall chargers short the D+ and D- ...
ArraysStartAtSeven's user avatar
8 votes
3 answers
749 views

Name of component on output side cable of a DC power adapter?

What is the name of this component (circled in red) of a charger? What are the uses of this component?
aravind ramesh's user avatar
16 votes
5 answers
17k views

How does a USB 2.0 Wall Charger negotiate current output?

I'm trying to use a mobile phone charger for my projects, and want a high current output. I have read this, however my measurements show something else. Here is a link to the Battery Charging ...
tgun926's user avatar
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1 vote
1 answer
2k views

Draw power from a portable mobile charger to power circuits

I usually power my beginner prototype circuits using mb102 power supply board, but it needs an external elimeter to draw power and then regulate it. I was looking for a portable solution for my 5 ...
hussainb's user avatar
  • 125
2 votes
2 answers
1k views

Is this a viable mini wind turbine setup?

I'm going to build my first wind turbine. I have already constructed the prop, 5 blades 50cm long from PVC pipes. I've searched for a decent sized motor and charge controller. The turbine will be ...
Pellepuffin's user avatar
0 votes
3 answers
3k views

Does a USB PD source supply any voltage to a non USB PD compliant USB C device? If yes, how much?

I have a 40W USB PD compliant charger from my ultrabook. I recently bought a pair of headphones (Sony WH-1000XM4) which can be charged using a USB C Plug. Sadly I can not find in the specifications of ...
user avatar
0 votes
1 answer
2k views

LiPo Charging Ciruit - Switching Help

I do understand that similar questions and maybe even the same question has been asked before, I've found them but unfortunately as a result of inexperience on my part I have been unable to adapt the ...
Robert Seal's user avatar
18 votes
4 answers
13k views

Cellphone charger has no transformer?

I opened up a really tiny mobile phone charger I have, to see how it is designed. The entire "charger" is integrated into a small 2-pin mains plug, 1 x 1.25 x 0.5 inch, that has an USB socket for the ...
Seemingly So's user avatar
12 votes
6 answers
26k views

Converting and Stabilizing output voltage of a dynamo hub

Preface - I don't know much about electronics :P I have ordered a Shimano dynamo hub for my bicycle. I have done a little homework and here are my findings about it: The output of the above ...
Raj Pawan Gumdal's user avatar
12 votes
1 answer
1k views

How to power a widget, while the li-ion battery is charging?

I am in need of a way to charge a 3.7V li-ion cell (probably an 18650 type) from a 4.5V - 20V input. That's not a problem, there are plenty of (switching) battery chargers around with that kind of ...
Thomas O's user avatar
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10 votes
2 answers
17k views

Why are these USB data lines conned to pull-up resistors?

I recently got a car lighter to USB adapter which I planned to use to charge my mobile phone. Unfortunately, the phone won't charge (and I know that the phone is capable of charging over USB port), so ...
AndrejaKo's user avatar
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7 votes
4 answers
22k views

Building a USB charger for camping

I was looking into building a battery powered USB charger for camping. It occurred to me that car chargers are pre-built and run off 12 V. If I made a battery pack out of 8x 1.5 V batteries in series ...
Lunix's user avatar
  • 73
6 votes
3 answers
2k views

Why AC supply is rectified first before stepping voltage down?

I have opened one of my phone chargers and was trying to understand how it works.. I found IC MB6F just at AC input which came out to be a bridge rectifier. My question is why AC is first rectified ...
Wupadrasta Santosh's user avatar
5 votes
1 answer
4k views

Dirt cheap NiCad charger

So sharptooth has a question up for creating cheap charger units that uses battery packs to charge a phone: Is designing and producing a dirt cheap charger really that hard? My question is the other ...
s3c's user avatar
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19 votes
3 answers
114k views

Using a 12V battery while simultaneously charging via solar panel

I have a couple of 12v batteries that I'd like to use to power a cooling apparatus while camping for several days. I also have a 15W solar panel I'd like to use to top-off the battery. Can I use the ...
nimble's user avatar
  • 201
11 votes
4 answers
12k views

Charging li-ion cell using constant-voltage only

Introduction Various resources [1] [2] state that the optimal method of charging a li-ion cell -- such as one found in a mobile phone -- is to charge at a constant current (usually <1C) until a ...
heypete's user avatar
  • 601
5 votes
1 answer
6k views

Smart charging circuit for NiMH battery pack

I want to build a solar powered charger for a niMh battery pack to run a microcontroller. What are the fundamentals of building a smart circuit that will not overcharge the battery and will also allow ...
Brian's user avatar
  • 153
4 votes
2 answers
2k views

How to lay out a schematic for review? Please critique

So, because I haven't posted a schematic for review before, I have no idea how to do it. Apparently, my previous attempt was poor. I got some actionable feedback, but I'm looking for more! I would be ...
Jon Watte's user avatar
  • 5,660
3 votes
3 answers
3k views

Mobile phone battery charger

I would like to know about the workings of mobile phone battery chargers. I know the basic principle, you take a transformer to bring it down to 9/6/3.7 volts then a bridge rectifier circuit and a ...
Rick_2047's user avatar
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2 votes
7 answers
18k views

Why is a laptop power supply output voltage different from its battery?

I hope you will not mind answering. This question has long been on my mind. Normally, the adapter output voltage is higher than that of the battery. In my laptop's case, the output voltage of the ...
AirCraft Lover's user avatar
1 vote
2 answers
3k views

How does this wireless charger work?

I want to understand the way this circuit works. The following are diagrams of the transmitter and receiver of a wireless iPod charging circuit. I have added a link to the instructable that describes ...
Undertherainbow's user avatar
0 votes
1 answer
945 views

USB charging at 4.3 volts

I'm trying to create a charger that knows how to switch between OTG and charging mode. The OTG side is working, and my Samsung S4 goes into charging mode. However, charging is really slow. It even ...
WayneDinh's user avatar
0 votes
1 answer
211 views

Charge controller for Li-ion or Li-Polymer battery

I am trying to work out the good charger for Mobile phones, which can serve as good performer for various smart phones out there in market these days & mostly using Li-ion battery. Charging has 4 ...
JP Singh's user avatar
-1 votes
2 answers
222 views

Solar panel lipo and usb

I connect a 5v 5w solar panel a usb port and a 3.7v 2.5A lipo with pcb. If I connect a phone to usb port it doesn't charge, but if I remove the battery from the circuit, it does. I suppose it's ...
Andrea's user avatar
  • 31
-1 votes
1 answer
2k views

What's the purpose of this bulky cylindrical part near the plug end of a laptop charger cord? [duplicate]

I want to fix my laptop charger cord, I used a multimeter to check the voltage and it gives me less than one volt. It feels very flexible near the plug, but I don't know if I can cut before or after ...
Pulse9's user avatar
  • 499
13 votes
2 answers
33k views

How can I use two TP4056 with two li-ion batteries, but single load?

I have two TP4056 modules (with protection circuit), which I am using to charge two batteries respectively, off a single power line. The modules are the ones that have charge output (B+/B-), and ...
Mr.M's user avatar
  • 165
10 votes
3 answers
9k views

Why some phones need a 5V charger although the battery needs 3.7V only?

I've many mobile (smart phone) chargers. The output of them is 5 volts but the battery needs 3.7v only. Why is it better to make a 5v charger then convert the 5v to 3.7v ? Why don't we just make a 3....
Michael George's user avatar
10 votes
2 answers
15k views

How does a battery balance and protection circuit work?

I am building a 4S LiPo battery pack that I would like to incorporate in a portable speaker project and I need to make sure the batteries will never require maintenance beside replacing them ...
Bogdan's user avatar
  • 602
7 votes
2 answers
2k views

How do snap-on induction charging systems not interfere with device functioning

There's a variety of snap-on wireless charging solutions on the market. For example, this one includes a charging mat and a plastic case that is put onto iPhone. I suppose the winding is in the ...
sharptooth's user avatar
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6 votes
2 answers
21k views

What might cause audible noise in an inductive charging system?

I have a pair of Qi-compatible wireless charging pads, and I've noticed that when a device is charging, the pad will emit a quiet but noticeable squeal in a relatively high frequency range. Perhaps it'...
dgw's user avatar
  • 173
6 votes
1 answer
5k views

Coin cell battery recharging circuit for RTC backup power

I am designing a system that contains an RTC to for displaying the date and time on a user interface, as well as log events with time stamps. In this particular case, the system gets powered-on at ...
wave.jaco's user avatar
  • 665
5 votes
6 answers
20k views

How to charge Laptop Li-ion Battery cells manualy?

I have received some Li-ion batteries which were originally used in Asus A2 Laptop battery original one and I would like to know if it is possible to charge each cells independently with some device ...
George's user avatar
  • 165
5 votes
5 answers
4k views

TP4056 module shutdown problem

Does anyone know why this TP4056 module shuts down in this configuration? If I bypass it, everything works and the measured current does not exceed the limit of the TP4056. Does not work: Works:
Quahetus's user avatar
4 votes
2 answers
2k views

Lithium Ion prolonged lifespan

According to the Battery University, charging a Li-ion cell to just 3.92 V is the optimal voltage to avoid stress and lithium plating. Problem is, nearly all consumer chargers focus on going to 4.2 V ...
sryan2580's user avatar
  • 117
4 votes
2 answers
5k views

Building an inverter to charge various devices

With all the power outages being caused by Hurricane Irene, I thought it might be useful to have an inverter that I could charge my cell phone with. Plug in battery power on one end, cell phone on ...
MGZero's user avatar
  • 179
4 votes
2 answers
3k views

Is there a reason GaN chargers stop at 65W?

During the last year or so we have seen commercial release of USB chargers utilizing GaN technology. For some reason it seems no products go higher than 65W. The Navitas reference platform was 65W, ...
chx's user avatar
  • 336
4 votes
1 answer
22k views

TP4056 Lithium Charger Module issue

Im having an issue with TP4056 Lithium Charger Module. Connected the battery 3.7v 150mah battery. When charging the red led is on but it never shuts off and no charge state is reached even after 1-2h ...
NccWarp9's user avatar
  • 185
4 votes
1 answer
700 views

Parallel charger circuits

I'm constructing a power supply based on solar cells backed by batteries. The solar cells deliver between 0 and 4 A, depending on the time of day, while the charger I plan on using, the LT3652, has a ...
gspr's user avatar
  • 194
3 votes
2 answers
4k views

MCP73831 Li ion battery charger problem with load sharing circuit

I am building a device which is being powered by single cell Li ion battery (1100mAh), i am using MCP73831 Li ion battery charger and controller in my design to charge the battery. I am using below ...
Mudassir Hussain's user avatar
3 votes
0 answers
2k views

How to charge LiPo battery using a wind generator?

For a home robotics project I want to fly a kite using a computer. For this to happen I need an electro motor up in the air (attached to the kite) which obviously needs a battery up there as well. ...
kramer65's user avatar
  • 485
3 votes
2 answers
8k views

On an Apple 12W USB Charger, how are the D+ and D- lines configured?

I'm looking for the voltages on the D+ and D- lines of an Apple 12W charger that corresponds to the 2.4 A output.
mmize's user avatar
  • 153
3 votes
1 answer
2k views

TP4056 & resistor at VCC

Could someone please explain me what is the 0.4Ω resistor at the Vcc pin (yellow color)? Why it is surrounded by a dashed rectangle? Should I add such kind of resistor when I design my circuit?
Efthymios Kalyviotis's user avatar
2 votes
2 answers
641 views

Charging a Phone With a Lower Current-Rated Power Supply

My friend's iphone charger exploded. She was charging an iPad with it. Since the iPhone power supply has a current rating of 1A while the iPad charges with a 2A current, many are blaming her that she ...
Simon Sultana's user avatar
2 votes
3 answers
4k views

USB type-c power supply (up to 20V 5A) from DC source

I have a custom made 5s power bank (30 x 18650 cells) and I want to make a power supply to charge my laptop using this power bank. It's not a big deal to make a 5V charger because I just have to hard ...
Tutankhamen's user avatar
2 votes
4 answers
27k views

Charging 2 Li-Ion Batteries via a single charger

I'm currently building a portable USB charger. It uses 2 Li-ion batteries in series connected to a USB port via a 5V regulated buck converter. While a single Li-ion battery would suffice for most ...
Alex Freeman's user avatar
2 votes
4 answers
17k views

How do we charge a small 12V battery from a large 12V battery bank

In a youth organization that I am part of we are building a traveling stand alone system, which will be put up on various fairs and music festivals. On one of the festivals there is a wish that we can ...
Mads Skjern's user avatar
2 votes
2 answers
6k views

Lithium Ion Cell balancing

I’m making a Lithium Ion charger circuit and successfully used a Texas Instruments bq2057c to charge 2 Lithium Ion cells in parallel (4.2V). Now I want to do the same with the cells in series (8.4V). ...
Nimyz's user avatar
  • 121
2 votes
3 answers
412 views

Is designing and producing a dirt cheap charger really that hard?

Recently one blog service (all text is in Russian) published a curious post. The author proposes to add mobile phone charging capability to each 4-pieces pack of AA alkaline batteries. The idea is ...
sharptooth's user avatar
  • 12.4k
2 votes
1 answer
2k views

Is it safe to charge a Li-Po battery at a lesser C rate than its usual routine?

On my Quad Copter I have a 5400mAh Li-Po battery (3S 11.1V) and its charger charges at 0.5 C since it takes 2 hours to charge the battery. That charger has broken down, I have ordered a replacement ...
Hanky Panky's user avatar
2 votes
4 answers
7k views

DIY NiCad charger

I have this Ryobi 12V NiCad cordless drill that was sitting in a drawer for the past 6 years or so due to dead batteries (2 of them). At least that's what I tought at the time but looking at it more ...
Zot Ditz Myo's user avatar