This discussion contains forward-looking statements, which are subject to certain risks and uncertainties, including, without limitation, those described elsewhere in this Form 10-Q and, in particular, in Item 1A of Part II hereof. Actual results may differ materially from the results discussed in the forward-looking statements. For a discussion of risks that could affect future results, see "Item 1A. Risk Factors." All forward-looking statements included in this document are made as of the date hereof, based on the information available to us as of the date hereof, and we assume no obligation to update any forward-looking statement, except as may be required by law.
We are a multi-market integrated semiconductor company. Our three principal product groups are: power semiconductors; integrated circuits, or ICs; and systems and radio frequency, or RF, power semiconductors.
Our power semiconductors improve system efficiency and reliability by converting electricity at relatively high voltage and current levels into the finely regulated power required by electronic products. We focus on the market for power semiconductors that are capable of processing greater than 200 watts of power. We also design, manufacture and sell integrated circuits for a variety of applications. Our analog and mixed signal ICs are principally used in telecommunications applications. Our mixed signal application specific ICs, or ASICs, address the requirements of the medical imaging equipment and display markets. Our power management and control ICs are used in conjunction with our power semiconductors. Our microcontrollers provide application specific, embedded system-on-chip, or SoC, solutions for the industrial and consumer markets.
Our systems include laser diode drivers, high voltage pulse generators and modulators, and high power subsystems, sometimes known as stacks, that are principally based on our high power semiconductor devices. Our RF power semiconductors enable circuitry that amplifies or receives radio frequencies in wireless and other microwave communication applications, medical imaging applications and defense and space applications.
Over the past three quarters, our net revenues have increased. Our product revenues from sales of power semiconductors have increased consistently while our product revenues from the sale of ICs was higher in the
September 2013quarter than in the prior two quarters. Over the same periods, we experienced increased sales each quarter in all major geographic regions, including the United States, Europeand the Middle Eastand the Asia Pacificarea, and in all of the major application markets, except the consumer products market and the medical products market. Following our acquisition of the Acquired MCU Business, we experienced growth in IC sales to the consumer products market during the September 2013quarter. Revenues from the medical products market fluctuated from quarter to quarter. Distribution revenues increased during the past three quarters as sales grew in the industrial and commercial market. Overall, our selling expenses have increased with higher revenues. Excluding certain acquisition-related expenses, our general and administrative expenses and research, development and engineering expenses, or R&D expenses, have remained relatively flat.