Hi Everyone, I have what I hope to be a simple problem. I'm working on modifying a battery pack for an old video game console (Sega Genesis Nomad to be exact) and I'm having some issues getting the charging circuit to work correctly. Below is a simple diagram of the circuit. In order to use the OEM wall wart, I decided to use a DC-DC buck converter. Everything seems to work as expected, with the exception of the DC-DC converter's LED being powered on all the time, even when removed from the power source. I don't want this, as it would drain the battery over time. I thought simply putting a diode (1n4007) between the buck converter and the battery's positive terminal would prevent current from flowing back in the converter and powering the LED, but that appears to have prevented the battery from charging correctly (Though, it did shut off the LED). Is there anything simple I am missing here?
Previously, I simply did these battery packs by installing a new DC jack and wiring it directly to the battery and load. That works fine, but requires a 7.4v power supply rather than the Sega OEM. Thanks in advance for any help, and sorry for the simple question. Please let me know if I need to provide more information.
EDIT: To clarify, the LED pictured is not the LED I'm having issues with. I installed that LED as a status light for when the power supply was plugged in. The LED in question is located on the buck converter just before the output.
Previously, I simply did these battery packs by installing a new DC jack and wiring it directly to the battery and load. That works fine, but requires a 7.4v power supply rather than the Sega OEM. Thanks in advance for any help, and sorry for the simple question. Please let me know if I need to provide more information.
EDIT: To clarify, the LED pictured is not the LED I'm having issues with. I installed that LED as a status light for when the power supply was plugged in. The LED in question is located on the buck converter just before the output.
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