Lawrence A Sample

US Patent:

39673120, Jun 29, 1976

Filed:

Nov 18, 1974

Appl. No.:

5/524425

Inventors:

Lawrence Ray Sample - Huntington Beach CA

Assignee:

Motorola, Inc. - Chicago IL

International Classification:

H04N 950

US Classification:

358 23

Abstract:

A silicon monolithic integrated circuit comprising a DC biasing network and three sets of full wave, synchronous, gated, transistor demodulators to demodulate the red, blue and green color different signals which are present in a composite television signal. The DC biasing network includes; a voltage regulator for providing a direct current voltage independent of variations in the magnitude of a power supply voltage the variations may be caused by voltage transients or varients in the temperature of the monolithic chip, and a direct current bias amplifier connected to the voltage regulator for providing a zero differential temperature coefficient direct current bias voltage to the outputs of the three sets of demodulators. Also disclosed is a blanking amplifier to facilitate direct current restoring at each of the outputs of the demodulators, the blanking amplifier being responsive to a blanking input signal. As a result, variations in the direct current voltage level at the output of the demodulators are severely attenuated.