MULTISTAGE AMPLIFIER AND INTEGRATED CIRCUIT

摘要

An initial-stage amplifier 1 that deals with microsignals and other amplifiers 2 and 3 separate a power source line, and both separated power source lines 4 and 8 are commonly connected to a power source pad 6. This enables avoidance of the occurrence of a large potential difference between the initial-stage amplifier 1 and other amplifiers 2 and 3 due to differences in currents pulled to the amplifiers 1 to 3, and can prevent the occurrence of noise arising from such potential difference. Also, feedback loops are differentiated by the initial-stage amplifier 1 and other amplifiers 2 and 3. This can also prevent unfavorable effects where a large signal would be fed back from the rear-stage amplifiers 2 and 3 to the initial-stage amplifier 1.