| 摘要 |
<p>A differential comparator includes first and second transistors for comparing an input signal to a reference signal during a comparison phase and circuitry for balancing the quiescent currents through the transistors. The circuitry includes a first current source (N1A) connected to the source of the first transistor (N1), a second current source (N1B) connected to the source of the second transistor (N2) and a selectively enabled impedance means (NFB) connected between the sources of the two transistors (N1,N2). Prior to each comparison phase the currents through the first and second transistors (N1,N2) are balanced (i.e. made approximately equal) by application of equal voltages to the gates of the two transistors (N1,N2) and cross-coupling the source potentials of the first and second transistors (N1,N2) to control the second and first current sources (N1B,N1A). <IMAGE></p> |
