I have an interesting case of iphone 7 that's had some rework done prior to this. The phone is working fine running off a battery, but when plugged in via a 5v lightning cable it's not charging, and it's not consuming much current (0.01A on my PSU, which could be anything 1-10ma based on lack of finer resolution of the meter).
If I remove the battery, and measure the voltage on the battery terminals there's voltage pulsing about 2x a second (tigris is trying to output 3.8v but shuts down). There's no obvious short on the battery line or pp_vdd_main
PP5v0_USB is ok at 5v
Tigris_LDO is pulsing
I replaced tigris, tristar, and tried a new dock flex to no change. What could cause Tigris output to pulse other than a short on the power line(s) considering the phone is working fine off a battery? Perhaps I missed a short on some secondary supply line?
If I remove the battery, and measure the voltage on the battery terminals there's voltage pulsing about 2x a second (tigris is trying to output 3.8v but shuts down). There's no obvious short on the battery line or pp_vdd_main
PP5v0_USB is ok at 5v
Tigris_LDO is pulsing
I replaced tigris, tristar, and tried a new dock flex to no change. What could cause Tigris output to pulse other than a short on the power line(s) considering the phone is working fine off a battery? Perhaps I missed a short on some secondary supply line?
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