| 摘要 |
The present invention relates to a improved feedback circuit for generating a quantized control signal representing the relation of a signal to be controlled relative to predetermined limits of at least one error signal window, the circuit comprising signal detecting means, a detected signal connected to error amplifying means for amplifying the error between the detected signal and a first reference signal, the output error signal of the error amplifying means connected to at least a first comparator means and second comparator means each configured to compare the error signal with one of the upper limit and lower limit of the at least one error signal window. The invention provides a circuit and method by which only one accurate comparator is needed and for the error windows only simple, inaccurate comparators can be used. Thus, accuracy of the distance between the defined error window levels is much more fixed because it is primary determined by mismatch of resistors and not by the offset of the used comparators. Further, the capacitive load on the feedback node is smaller, which leads to a better response time. Furthermore, the current consumption is considerably less. Moreover, the circuit will be smaller. Finally, yet importantly, the overall offset of the output voltage is comparable to the offset in the standard solution. |
