When using a cell phone, a(n) converter chip changes your voice's sound waves into digital signals.

analog-to-digital

Explanation: Analog-to-digital converters as the name implies simply refers to components which are used to convert continuous analog signals into a discrete analog outputs so they it can be read and processed by a microprocessor. The microprocessors are unable to depict and read analog signals which could be gathered from sound, light or water wave sources. This wave sources are then sampled, processed and sorted into levels by the analog-to-digital converter before being sent to the microprocessor so that the waves can be read.