Transistor Museum Oral History Bill Gutzwiller Page 13 GE SCR Triac

EARLY POWER SEMICONDUCTOR HISTORY AT GE

An Interview with F.W. “Bill” Gutzwiller

The Early History of the Silicon Controlled Rectifier

These are sections from two of the key patents awarded to Bill Gutzwiller, as discussed in this Oral History. Both patents relate to major inventions associated with power semiconductors. The top patent (3,222,583) was filed soon after the invention of the SCR and reflects one of the first circuits developed by Bill to utilize the new technology. This basic circuit approach is in use today in millions of speed controls for appliances, hand tools and sewing machines. The bottom patent (3,275,909) is the basic TRIAC AC switch used worldwide in almost every lamp dimmer, static AC switch and solid-state electric heating control.

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