I'm trying to come up with a way to wire a portable speaker. I'd like to include two separate jacks, one for an AC/DC power supply, one to charge a li ion battery.
I'd like to use switched jacks to try to make this dummy proof so that when a plug is inserted into the power jack, the battery is disconnected to keep the power supply from damaging the battery.
I'd also like to make it so that when the charger is plugged into the charging jack, the battery is disconnected from the amp so I'm not draining current from the battery at the same time that it's being charged.
I've attached a (poor) drawing of a circuit that I think will achieve the first goal, but I don't know how to use a switched jack for the charger to achieve the second goal.
I'd like to use switched jacks to try to make this dummy proof so that when a plug is inserted into the power jack, the battery is disconnected to keep the power supply from damaging the battery.
I'd also like to make it so that when the charger is plugged into the charging jack, the battery is disconnected from the amp so I'm not draining current from the battery at the same time that it's being charged.
I've attached a (poor) drawing of a circuit that I think will achieve the first goal, but I don't know how to use a switched jack for the charger to achieve the second goal.
Attachments
I was thinking about it more and I think this ought to do it?
Looks good! Go for it!

Hi,
You can do it with 3 diodes. See the attached corrected drawing. If you want the power supply to charge the battery remove diode 2.
I see what you are doing there. It makes sense. Are the diodes necessary though if I use the switches on the jacks? I thought about putting a diode at #2 just as a backup in case the switch fails.
Hi,
The diodes replaced the switches. The diodes are used for isolation in case you power off either the power supply or the battery charger. Be careful in which battery charger you used. There are cheap battery chargers that are what we call pulsating DC. They do not have capacitors to smooth or filter the voltage output.
The diodes replaced the switches. The diodes are used for isolation in case you power off either the power supply or the battery charger. Be careful in which battery charger you used. There are cheap battery chargers that are what we call pulsating DC. They do not have capacitors to smooth or filter the voltage output.
Hi,
The diodes replaced the switches. The diodes are used for isolation in case you power off either the power supply or the battery charger. Be careful in which battery charger you used. There are cheap battery chargers that are what we call pulsating DC. They do not have capacitors to smooth or filter the voltage output.
I understand. Thanks for explaining.
I was planning to get a battery pack and charger from battery space. It's a little more expensive than buying the cheap stuff from amazon or ebay, but I understand that they are pretty reputable and at least you know what you are getting.
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