Patent ID: 6127868
Filing Date: 2000-10-03
Classification: G04F,H03K

Abstract:
A comparison circuit comprising:first and second differential pairs, each having a first current path with a control element, a second current path with a control element, and a merged current path coupled to a ground voltage;a first current mirror for providing a mirrored current source coupled from a supply voltage line to the first current path of the first differential pair, and coupled to the second current path of the second differential pair; anda second current mirror for providing a mirrored current source coupled from the supply voltage line to the second current path of the first differential pair, and coupled to the first current path of the second differential pair;a first reference node coupled to the control element of the first current path of the first differential pair, the first reference node for receiving a first reference signal;a second reference node coupled to the control element of the second current path of the second differential pair, the second reference node for receiving a second reference signal;a testing node coupled to the control element of the second current path of the first differential pair and coupled to the control element of the first current path of the second differential pair, the testing node for receiving a testing signal;wherein the current drawn through the second current mirror based on the testing signal in conjunction with the second reference signal is to be compared to the current drawn through the first current mirror based on the first reference signal in conjunction with the testing signal; andwherein the current drawn through the second current mirror based on the testing signal in conjunction with the first reference signal is to be compared to the current drawn through the first current mirror based on the second reference signal in conjunction with the testing signal.