Analog multiplexer core circuit and analog multiplexer circuit

摘要

An analog multiplexer core circuit (120A) includes a differential pair (121) that includes two transistors (Q1, Q2), a differential pair (122) that includes two transistors (Q3, Q4), a differential pair (123) that includes two transistors (Q5, Q6), and a constant current source (124) that causes a current (I EE ) to flow. This analog multiplexer core circuit (120A) time-multiplexes two analog signals (Ain1, Ain2) and outputs a time-multiplexed analog signal (Aout). Each emitter resistor (R EA 1, R EA 2, R EA 3, R EA 4) is connected to a corresponding one of the transistors (Q1, Q2, Q3, Q4). At this time, a relation of "R EA ·I EE ‰¥ the amplitude of an input analog signal" is satisfied. As a result, linearity of response can be ensured by expanding the linear response input range of the differential pairs (121, 122).