| 摘要 |
An automatic offset control circuit comprises a differential output preamplifier (102) having an offset adjustment function, further comprising an average detector (106), a peak detector (107), and a differential input amplifier (108). The average detector (106) generates a reference voltage representing an average value of a positive output (V+) and a negative output (V-) of the preamplifier (102). The peak detector (107) outputs a peak voltage representing a peak of the negative output (V-) of the preamplifier (102). The differential input amplifier (108) compares the peak voltage with the reference voltage to output an offset adjustment signal to the preamplifier (102). The offset adjustment signal is obtained based on a difference between the reference voltage and the peak voltage. A bottom detector (109) may be used instead of the peak detector (107), provided a bottom value is detected using the positive output of the preamplifier. <IMAGE> |
