A precision slope polarity switch for a monolithic telephone- quality deltamodulator
J. Price, S. Kelley · 1977
THIS PAPER will discuss a monolithic continuously variable slope deltamodulator capable of telephone quality digital voice transmission; Figure 1. It functions as either encoder or decoder, selectable by a logic input. The circuit is fabricated with a standard linear process which includes I?L, ion-implanted resistors, high gain PNPs, and laser trimming. A unique laser trimmed precision slope polarity switch is used to achieve telephone quality performance.