Patent ID: 9360505
Filing Date: 2016-06-07
CPC Classification: G01R,H03G,H03K

Claim Text:
1. A squelch detector, comprising: a current steering circuit generating a first current to a node c, generating a second current to a node d, generating a third current to a node e, and generating a fourth current to a node f; a first differential pair circuit connected with the node c and the node d, wherein the first differential pair circuit receives a first reference voltage and a second reference voltage, and controls the second current and the first current, so that a difference between the second current and the first current is equal to a current difference; a second differential pair circuit connected with the node e and the node f, wherein the second differential pair circuit receives a first input signal and a second input signal, and generates a fifth current and a sixth current; a current sensing circuit connected with the node e, the node f, a node g and a node h, wherein according to the third current, the fourth current, the fifth current and the sixth current, the current sensing circuit generates a first mirroring current to the node g and generates a second mirroring current to the node h; a current-to-voltage converter connected with the node g and the node h, wherein the current-to-voltage converter adjusts a first voltage level of the node g according to the first mirroring current and adjusts a second voltage level of the node h according to the second mirroring current; and a logic circuit connected with the node g and the node h, and generating a detected signal.