An integrated circuit such as, for example a graphics processing unit (GPU), having an on-chip analog to digital converter (ADC) for use in overcurrent protection of the chip is described, where the overcurrent protection response times are substantially faster than techniques with external ADC. A system-on-chip (SoC) includes the integrated circuit and a multiplexer arranged externally to the chip having the ADC, where the multiplexer provides the ADC with a data stream of sampling information from a plurality of power sources. Methods for overcurrent protection using an on-chip ADC are also described.