What is a frog
A frog (or “toad,” as these devices are also called) is easily recognized by two springy wires on the top cover, which are moved apart to the required distance - thanks to this, they can be docked with various batteries.
It is these contacts that should be connected to the battery, which was previously removed from the phone. That is, the device is only suitable for removable batteries (which means this device is useless for owners of the iPhone and many other modern models from other manufacturers).
The frog is able to transfer energy to lithium batteries in the simplest possible way. Moreover, in some cases it can charge even faster than the included charger.
Checking functionality
On the side surface of the classic “frog” type there is a button marked with the inscription TE , i.e. "testing". It is used to check the polarity of the connected battery. Pressing this button once turns on the CON diode to turn green, confirming that everything was done correctly.
Selfie stick - connection and setup
If the CO N does not light up , press the button on the right, which changes the polarity.
If no buttons are found on the side panels of the device, most likely the model tests polarity automatically .
Also, the indicators may not light up if the battery has moved to the side and its contacts no longer interact with the charger terminals.
Types of universal phone chargers
Now in stores you can find the following options for universal chargers:
- car (connects to the cigarette lighter);
- with a USB port (has a corresponding USB connector);
- with a plug for power supply from a household electrical outlet (standard).
In addition, recently models have appeared on the market that simultaneously have both a USB port and a plug.
Also, all modern frogs can be divided into automatic and semi-automatic. The main difference between the first and second types is the number of LEDs: the “automatic” has three, the “semi-automatic” has four. The fact is that automatic models are able to independently determine the polarity, and therefore the polarity reversal button (usually it is labeled CO) is absent on them.
Tips for beginning designers
- Carefully press down the fold lines and corners. Especially important for the jumping frog.
- For the first experience, it is better to use sheets from a school notebook. It is easier to practice correct folding on soft paper.
There are many other options on how to make an origami frog. Modular origami is considered the most complex. To make a model, you need to make more than 400 modules, then connect them into the model.
Both children and adults are interested in the art of origami. We must remember that it is better to practice the technique on simple models, gradually moving on to more complex ones.
Before you start working with the craft, you need to carefully study the diagram, read the text instructions and watch master classes.
Frog charger circuit
The concept of a classic frog is quite simple. The two moving contacts connected to the battery come from the controller. The role of the controller is performed by microcircuits of a certain complexity. The controller's task, in particular, is to compare the voltage on the battery with the internal reference one. When these two indicators become identical, the controller will turn off the power supply.
Another significant part of universal charging is a bridge AC/DC converter with a built-in key for connecting the battery to the power source (mains). It is located at the very beginning, in front of the controller and contacts. The purpose of this unit is to convert alternating voltage to direct voltage.
Homemade toad
After analyzing several Frog memory schemes, I settled on one of them. I decided to make it as an attachment for charging NOKIA (I think many people have them, and I have several of them lying around) to charge a Li-ion 18650 battery. In the NOKIA charger itself, the output from the transformer is almost 7V, which should be enough for the attachment.
For the battery itself, you will need a battery compartment to mount it on the side of the case. On the lid there is an output of four LEDs and a microswitch. In the meantime, a signet on CMD and simple radio elements has been developed for the circuit, installed on top of the board. Download it here.
The enclosed signet has already been mirrored; please send it for printing immediately. The photo simply shows the arrangement of the elements as it should be.
Next, I soldered a separate memory card and tested it – it works great! With the specified details, the charger output is 4.2V. I put a used battery on charge and the charge rises. The LM358 chip was installed soldered, taken from God knows where. I used a power supply with a 6V 0.45A output.
The circuit diagram was drawn and checked by Igoran .
Discuss the article CHARGER FROG
Schematic, printed circuit board and photographs of a repeatedly tested FM transmitter.
When is it recommended to use a frog?
Theoretically, the frog can be used with the same intensity as regular exercise. But in practice, it often serves as a spare charger. If the original charger is lost, then universal charging will allow you to stay in touch.
Sometimes, after losing the charger that came with the kit, it turns out that finding the right analogue is very difficult. This is true primarily for old models of mobile phones that are no longer produced, but remain in use. A frog in this case can save the situation. And if for some reason the battery connector is broken, the toad can also help out.
A universal charger will certainly come in handy for those who have two or more phones of different models. When you go on a trip, you don’t have to take a bunch of power supplies with you, but get by with this one device.
Important! It is the frog that is used “to bring back to life” completely discharged lithium batteries of mobile devices. The universal charger controller is not capable of blocking the supply of voltage to a severely discharged battery, and in this particular case this is an advantage, not a disadvantage.
Prices
The cheapest chargers cost from 100 rubles. On average you will have to pay about 200 rubles. Devices with LCD screens will cost 250–300 rubles. Chinese devices cost 1–2 dollars on Aliexpress, you can find them cheaper, but they have a drawback: they often have a local, not European plug.
Recently, hybrids have appeared for installing one battery and equipped with an additional one or two contacts for connecting a USB cable - the price starts from 500 rubles. In fact, they also serve as a power supply.
How does a frog charger work?
One of the obvious advantages of this device is its small dimensions. This allows you to easily carry it in a backpack, bag or pocket and plug it into any suitable outlet. The classic frog runs on 110–220 Volt power. In this case, the output voltage is much lower (for example, 4.2 Volts). As for the output current, it is equal to several hundred milliamps.
The charge occurs in the device automatically and is controlled by the microcircuit. When the maximum possible charge level is reached, the device turns off itself. That is, nothing bad will happen if, instead of the required three hours, the battery is in universal charging for a couple of hours longer. In general, the time to fully charge a battery (digital camera, smartphone, player, etc.) depends on the capacity. As a rule, we are talking about a period of 1.5 to 5 hours.
How to use a frog to charge your battery
Of course, a device such as a frog is accompanied by instructions from the manufacturer. But it is often written in a foreign language (in particular, Chinese), and therefore the user has to figure it out on his own.
The battery must be inserted into the frog so that the contacts of the universal charger are located on the plus and minus terminals of the battery. If the battery has three or four terminals, you should use the two outermost ones.
If the polarity was chosen correctly, then when you press the TE (test) button, the green CON LED will light up. After this, you can safely insert the entire structure into the outlet. As a result, the PW (network) indicator should light up, and then the CH (Charge) indicator. And when charging is complete, the corresponding FUL LED will light up (full charge).
If the CON diode does not want to light up, then most likely you have a very low battery. A battery with a nominal voltage of 3.6 Volts may well discharge below 3.2 Volts, and in such a situation the mobile phone will not show any signs of life even when connecting the “native” charger.
The solution is simple: the battery must be connected randomly, in any polarity, to the frog and plugged into the network for five minutes - the CH diode should blink. The purpose of universal charging is to give a strong boost to the battery. And then it can be charged in the usual way.
Attention! Sometimes, with a damaged battery, the frog may show a full charge of FUL, even if this is not true. It is unlikely that you will be able to fix this on your own; you will need to call a professional technician or simply throw away the battery.
Basic malfunctions and methods for their elimination
Device malfunctions are judged by the incorrect operation of the device:
- If FUL and PW light up immediately after connecting the device, most likely there is no contact between the frog and the battery. You need to move the battery closer to the contacts;
- It happens that when it is still far from being fully charged, the “clothes clip” shows that the battery is fully charged – “FULL” is lit. This happens when the battery is faulty - charging current does not flow.
The design of the “Toad” is not complicated, so it is not difficult to make it yourself.
Precautions
- Always insert a lithium battery between the terminals first. And only then can the device be plugged into the outlet. If you do the opposite, you can get a noticeable electric shock.
- There should be no flammable materials near the universal charger plugged into the outlet.
- The frog is designed for lithium batteries only and should not be used to charge other types of batteries.
- After the battery is charged, it is advisable to unplug the universal device from the network.
Do you have any questions about the Frog or something to add? Then write to us about it in the comments, this will make the material more useful, complete and accurate.
Transformer non-automatic chargers
These devices do not have protective circuits. If the battery is kept under voltage, the electrolyte from the nickel-metal hydride battery may boil away. As a result of this process, the capacity decreases and the power of the device decreases. At the moment, such devices are practically out of use, despite their durability and reliability. If you put a “frog” next to this device to charge your phone, you can immediately clearly see how far progress has come in the development of technology.
