I need to build a simple opamp based preamp/buffer for an automotive project.
The Buffer is going to be used to interface an MP3 player to a car stereo. the problem is, a ground loop is created when the charger is plugged into the MP3 player as well.
Now the ugly cheap and easy solution is a radio shack ground loop isolator. yuck.
I need to come up with a better solution to do this.
The audio coming out of the MP3 player is unbalanced with a common ground. I have balanced inputs available going into the car stereo, or it can be used unbalanced. The radio shares ground with power, data and audio internally.
I dont have much room inside the case to hang iron and getting small, high quality iron is difficult and costly. so i am looking for some other solution.
Can i simply tie the opamp input neg side to ground through a 100 ohm resistor? Would that be enough to break the ground loop? I thought i had seen that done elsewhere. But wouldnt noise on the ground line then inject noise into the neg side of the opamp?
Help would be greatly appreciated.
Zc
The Buffer is going to be used to interface an MP3 player to a car stereo. the problem is, a ground loop is created when the charger is plugged into the MP3 player as well.
Now the ugly cheap and easy solution is a radio shack ground loop isolator. yuck.
I need to come up with a better solution to do this.
The audio coming out of the MP3 player is unbalanced with a common ground. I have balanced inputs available going into the car stereo, or it can be used unbalanced. The radio shares ground with power, data and audio internally.
I dont have much room inside the case to hang iron and getting small, high quality iron is difficult and costly. so i am looking for some other solution.
Can i simply tie the opamp input neg side to ground through a 100 ohm resistor? Would that be enough to break the ground loop? I thought i had seen that done elsewhere. But wouldnt noise on the ground line then inject noise into the neg side of the opamp?
Help would be greatly appreciated.
Zc