I'm trying to replace the rechargeable battery in a toy with a direct power supply because the battery life is too short and charging takes forever. In the past, when I've attempted this, the circuit board often gets fried. I've ensured the voltage of the power supply matches that of the battery, but I'm suspecting it might be drawing too much current. How can I figure out the maximum current the toy's circuit board can handle? Or could there be other factors that are causing the board to fail?
3 Answers
You should start by identifying what type of battery is currently being used in the toy. Each type—AAA, AA, C, or D—has a voltage of 1.5V, so you can calculate the total voltage based on the number of batteries. For instance, if there are three batteries, a 5V power supply should work well.
Have you considered using battery terminators? They're simple plastic replacements with wires that can connect directly to your power supply. They usually cost around $5 on sites like AliExpress.
You just need to ensure the voltage is matched, but here's the kicker: the current rating of your power supply is a maximum limit, not the amount it pushes through. The toy will only pull what it needs based on its design.
That’s true, but don't forget to calculate how much current the toy actually requires. Make sure you use a power supply that can provide a bit more than that max current, or you'll still run into problems.