Hawaslsh
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Hello,
I have a DC/DC converter that was designed using Ti's wbench. The circuit uses the LMR33640. I posted the schematic below, and I followed the layout suggested by Ti and the wbench software. The converter seems to work as expected. I supply and input of 12V, and using an electronic load I can draw the desired 2-3 amps. There are test points for ground and +5 next to the regulator for an oscilloscope. Under load, the output doesn't look too bad, maybe 30-35mV p-p around 5V.
When i plug in almost all USB devices they begin to charge. Power packs, amazon fire, all cheapo Chinese kids' toys. However, not my Iphone! It's an old Iphone S. The phone will charge in all other instances: wall plugs, computer's USB plug... etc. Is there something special about charging Iphones I am not aware of? Or is my regulator too noisy?
Happy to provide much more context, just wanted to ensure I am not missing something apple specific before going into more details.
Thanks in adance,
Sami
I have a DC/DC converter that was designed using Ti's wbench. The circuit uses the LMR33640. I posted the schematic below, and I followed the layout suggested by Ti and the wbench software. The converter seems to work as expected. I supply and input of 12V, and using an electronic load I can draw the desired 2-3 amps. There are test points for ground and +5 next to the regulator for an oscilloscope. Under load, the output doesn't look too bad, maybe 30-35mV p-p around 5V.
When i plug in almost all USB devices they begin to charge. Power packs, amazon fire, all cheapo Chinese kids' toys. However, not my Iphone! It's an old Iphone S. The phone will charge in all other instances: wall plugs, computer's USB plug... etc. Is there something special about charging Iphones I am not aware of? Or is my regulator too noisy?
Happy to provide much more context, just wanted to ensure I am not missing something apple specific before going into more details.
Thanks in adance,
Sami