A simple but very useful charger that was put on the market many years ago ( first seen on a birdcage ) .. usually known as a spider charge or insect charge 🙂 The power is low, it charges for a long time, but the mechanical design is different in size, mobile phone, designed to fit and charge the battery of many devices. Charge circuit built on LM358 opamp
The high-resolution scheme of the same unit and a similar scheme;
The battery to be charged is switched on by opening the clamping system of the device.
The clamps are then set to sit on the positive (+) and negative (-) poles of the battery.
Then the “TEST” button is pressed. (K1 TE Button on the schematic)
As soon as the adapter is attached to the prize, “PW” will be lit steadily red, and “CH” will start to flash green.
This is a sign that the battery is starting to charge.
If the “CH” led does not light up, you have misplaced the polarity of your battery. By pressing the “CO” button you can change the charger polarity automatically.
When charging finishes and the battery is full, “PW” starts flashing bright red.