Patent ID: 6822513
Filing Date: 2004-11-23
Classification: H03F

Abstract:
A differential amplifier comprising the following:a first differential amplifier comprising: first and second input n-type field-effect transistors; first and second current load p-type field-effect transistors, a source terminal of each of the first and second current load p-type field-effect transistors coupled to a high voltage source, a drain terminal of the first current load p-type field-effect transistor coupled to a drain terminal of the first input n-type field-effect transistor, and a drain terminal of the second current load p-type field-effect transistor coupled to a drain terminal of the second input n-type field-effect transistor; and a current source n-type field-effect transistor having a drain terminal coupled to a source terminal of both the first and second input n-type field-effect transistors, the current source n-type field-effect transistor having a source terminal coupled to a low voltage source; a second differential amplifier comprising: first and second input p-type field-effect transistors, a gate terminal of the first input p-type field-effect transistor coupled to a gate terminal of the first n-type field-effect transistor, a gate terminal of the second input p-type field-effect transistor coupled to a gate terminal of the second input n-type field-effect transistor, first and second current load n-type field-effect transistors, a source terminal of each of the first and second current load n-type field-effect transistors coupled to the low voltage source, a drain terminal of the first current load n-type field-effect transistor coupled to a drain terminal of the first input p-type field-effect transistor, and a drain terminal of the second current load n-type field-effect transistor coupled to a drain terminal of the second input p-type field-effect transistor; and a current source p-type field-effect transistor having a drain terminal coupled to a source terminal of both the first and second input p-type field-effect transistors, the current source p-type field-effect transistor having a source terminal coupled to the high voltage source; a first hysteresis inducing p-type field-effect transistor having a drain terminal coupled to the drain terminal of the first current load p-type field-effect transistor, having a source terminal coupled to a high voltage source, and having a gate terminal coupled to a drain terminal of the second input n-type field-effect transistor; a second hysteresis inducing p-type field-effect transistor having a drain terminal coupled to the drain terminal of the second current load p-type field-effect transistor, having a source terminal coupled to a high voltage source, and having a gate terminal coupled to a drain terminal of the first input n-type field-effect transistor; a first hysteresis inducing n-type field-effect transistor having a drain terminal coupled to the drain terminal of the first current load n-type field-effect transistor, having a source terminal coupled to a low voltage source, and having a gate terminal coupled to a drain terminal of the second input p-type field-effect transistor; and a second hysteresis inducing n-type field-effect transistor having a drain terminal coupled to the drain terminal of the second current load n-type field-effect transistor, having a source terminal coupled to a low voltage source, and having a gate terminal coupled to a drain terminal of the first input p-type field-effect transistor.