hi me again.
So I am using TNY290 and a 749118205 for two 5V outputs. I have included a schematic from the application notes that shows multiple outputs. Okay so I have it set up so that both outputs go through their respective 20kOhm resistor to a divider of a 10kOhm resistor to ground and this feeds the reference pin on the TL341. But I have only one feeding the opto isolator and it is that one that is being properly regulated. The one that is not feeding the opto isolator is reading 3.90V at no load on the either output and 7V with load on the other. Mind you all the components on the protoboard are the exact same for both outputs. (ive inlcuded an example of what I am trying to show from ltspice ignore the item name for the opto that was just whatever)
I can get both outputs to be the same if I feed both outputs to the optoisolator but I dont understand why I should have to do that the schematic from the application notes does not do that and the notes also make no mention of preload or anything like that.
I need both to be close as possible to 5-5.5V for most usb devices to accept it and start charging
So I am using TNY290 and a 749118205 for two 5V outputs. I have included a schematic from the application notes that shows multiple outputs. Okay so I have it set up so that both outputs go through their respective 20kOhm resistor to a divider of a 10kOhm resistor to ground and this feeds the reference pin on the TL341. But I have only one feeding the opto isolator and it is that one that is being properly regulated. The one that is not feeding the opto isolator is reading 3.90V at no load on the either output and 7V with load on the other. Mind you all the components on the protoboard are the exact same for both outputs. (ive inlcuded an example of what I am trying to show from ltspice ignore the item name for the opto that was just whatever)
I can get both outputs to be the same if I feed both outputs to the optoisolator but I dont understand why I should have to do that the schematic from the application notes does not do that and the notes also make no mention of preload or anything like that.
I need both to be close as possible to 5-5.5V for most usb devices to accept it and start charging
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