Three-wire three-level digital interface

摘要

A receiver (100) for a three-wire digital interface, comprises a first resistive element (R1) coupled between a first input terminal (A) and a first junction node (JA), a second resistive element (R2) coupled between a second input terminal (B) and a second junction node (JB), and a third resistive element (R3) coupled between a third input terminal (C) and a third junction node (JC). A network (70) comprising first second and third network terminals (71, 72, 73) is coupled to, respectively, first, second and third junction nodes (JA, JB, JC). The network has substantially the same impedance between all pairs of the first, second and third network terminals. A first comparator (C1) has a non-inverting input (10) coupled to the first input terminal (A), an inverting input (12) coupled to the second junction node (JB), and an output (14) coupled to a first output terminal (AJ). A second comparator (C2) has a non-inverting input (20) coupled to the first input terminal (A), an inverting input (22) coupled to the third junction node (JC), and an output (24) coupled to a second output terminal (AK). A third comparator (C3) has a non-inverting input (30) coupled to the second input terminal (B), an inverting input (32) coupled to the third junction node (JC), and an output (34) coupled to a third output terminal (BJ). A fourth comparator (C4) has a non-inverting input (40) coupled to the second input terminal (B), an inverting input (42) coupled to the first junction node (JA), and an output (44) coupled to a fourth output terminal (BK). A fifth comparator (C5) has a non-inverting input (50) coupled to the third input terminal (C), an inverting input (52) coupled to the first junction node (JA), and an output (54) coupled to a fifth output terminal (CJ). A sixth comparator (C6) has a non-inverting input (60) coupled to the third input terminal (C), an inverting input (62) coupled to the second junction node (JB), and an output (64) coupled to a sixth output terminal (CK).