Re: Harman/Kardon Onyx Bluetooth Speaker - No Power
Yes, and now we start to get a clearer picture.
So, it seems point Power_ButA supplies power to the button. When the button is not pressed, power does not flow through it, so point Power_ButB is at 0v.
When the button is pressed, current flows from Power_ButA, through the switch, and into Power_ButB, bringing it high.
To do something useful, Power_ButB will be connected to the input of some other circuitry, to perform some task related to power on.
What you probably need to do now is follow the trace(s) from Power_ButB and find out where it goes and what it's supposed to be activating. Then we need to look at what it gives power to when pressed and see if that is doing what it should be.
That big current draw is likely a secondary power supply (one or more of those DC-DC converters) kicking in and a capacitor charging up or such. How long does it draw that amount of current for?
Originally posted by caphair
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So, it seems point Power_ButA supplies power to the button. When the button is not pressed, power does not flow through it, so point Power_ButB is at 0v.
When the button is pressed, current flows from Power_ButA, through the switch, and into Power_ButB, bringing it high.
To do something useful, Power_ButB will be connected to the input of some other circuitry, to perform some task related to power on.
What you probably need to do now is follow the trace(s) from Power_ButB and find out where it goes and what it's supposed to be activating. Then we need to look at what it gives power to when pressed and see if that is doing what it should be.
Originally posted by caphair
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