The ever-increasing reliance on electronic devices which utilize AC power highlights the problems associated with the unexpected loss of power from the electrical grid. In places where the electrical infrastructure is not well-developed, brown-outs can prove fatal when electronic medical instruments become unusable. Therefore, there is a need for inexpensive and reliable pure-sine wave inverters for use with medical devices in the underdeveloped world. This report documents the development of one component of an uninterruptible power supply, the DC-to-AC inverter. Through the use of analog signal processing techniques, a prototype which efficiently and accurately emulates the pure-sine wave power present on the power grid was created. The three-level PWM system within this report is created with the possibility of a feedback-regulated system to be implemented in the future.