KNOWPIA
WELCOME TO KNOWPIA
Karl D. Swartzel Jr. 
Summary
Karl Dale Swartzel Jr. (June 19, 1907 – April 23, 1998) was the inventor of the operational amplifier (or 'opamp'). He filed the patent for the 'summing amplifier' in 1941 when working at Bell Labs.[1]
References edit
- ^ US 2401779, Karl D. Swartzel Jr., "Summing amplifier", published 11 June 1941, assigned to Bell Telephone Labor Inc.