Diosdado P. Banatao (born May 23, 1946) is a Filipino entrepreneur and engineer working in the high-tech industry,[2] credited with having developed the first 10-Mbit Ethernet CMOS with silicon coupler data-link control and transceiver chip, the first system logic chipset for IBM's PC-XT and the PC-AT, and one of the first graphical user interface (GUI) accelerators for personal computers.

After high school, he pursued his Bachelor of Science in Electric Engineering from the Mapúa Institute of Technology and graduated cum laude.

[9] After finishing his master's degree, Banatao worked with different technology companies such as the National Semiconductor, Intersil, and Commodore International where he designed the first single chip, 16-bit microprocessor-based calculator.

[2] In 1981, he developed the first 10-Mbit Ethernet CMOS with silicon coupler data-link control and transceiver chip while working in Seeq Technology.

[4] In 1984, Banatao and his business partner Francis Siu, founded a high-technology company, Moston, starting with a capital of half a million US dollars.

The company developed system logic chip set for IBM's PC-XT and the PC-AT.

In 1989, Banatao launched his third start-up company, S3 Graphics, with Yara in Santa Clara, California.

In 1996, the company became the leader of the graphic-chips market, beating a strong competitor, Cirrus Logic, Inc.