Early work in electrowetting on dielectric (EWOD) devices has demonstrated their great potential in microfluidics; however, further work is needed to integrate EWOD technology into a system deployable for point-of-care (POC) diagnostics. This research is aimed at providing enabling technologies that foster a development path of EWOD devices using a process similar to the development of application-specific integrated circuits (ASICs). A field-programmable lab-on-a-chip (FPLOC), which allows designers to electrically program the prefabricated chip into EWOD applications, was fabricated and demonstrated based on novel microelectrode dot array (MEDA) architecture. The MEDA architecture proposes a standard EWOD component called “microelectrode cell”, which can be dynamically configured into microfluidic components to perform microfluidic operations of the biochip. The FPLOC is the first EWOD biochip fabricated by the standard low-voltage complementary metal-oxide-semiconductor (CMOS) technology, which allows smooth on-chip integration of microfluidics and microelectronics. A total of 900 droplet detection electrical circuits were integrated into the chip and a real-time droplet location map could show shapes and locations of all droplets on the chip. The daisy-chained control structure of the MEDA architecture allowed individual control of 900 microelectrodes by only using three control pads. This control structure was also leveraged to add the built-in self-test (BIST), which was proven to be very useful in diagnosing the chip, of the FPLOC. The FPLOC successfully demonstrated seamless hierarchical field-programmability. Compared to conventional bottom-up and full-custom design approaches, the FPLOC brings microfluidic technology closer to POC diagnostics by providing biochip designers with CAD support at a level similar to that of the semiconductor industry, without the time-consuming and costly process of hardware design, testing, and maintenance.