Charge and stereo input at same time

I have an iPhone 6s Plus. I have a Shure MV88+ external stereo microphone. The mic connects to the phone via lightning connection. It sends stereo L/R signal into the iPhone and needs power from the iPhone. That works fine. My question is: how do I charge the phone and use the mic at the same time. The Belkin lightning splitter that is available at Apple store advertises that it is for charging and listening to headphones at the same time. Basically charging the phone and stereo audio out at the same time. That adapter does not work for audio in. I tried it. Does anyone know what to use to charge and send stereo audio in thru the lighting connector on an iPhone? Or if it is even possible?