| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the matter of a photoelectric converter incorporating a gain switch function that, when the amount of bias current is switched according to a gain mode in order to accelerate the frequency characteristics, VBE voltage of a transistor constituting a clip circuit is varied by the difference in amount of bias current, and thereby the clip voltage differs for every gain. <P>SOLUTION: The photoelectric converter comprises a clip circuit where the emitter of a PNP transistor is connected with the output of an operational amplifier 103, a resistor 15 and a current source 16 are connected with the base of the PNP transistor, and a reference voltage is connected through the resistor 15. Consequently, the current source 16 independent of the resistor 15 can set a clip voltage depending on the gain, and recording/reproduction of each recording medium can be dealt with by switching the clip voltage to an optimal value depending on the gain in a gain switching amplifier. <P>COPYRIGHT: (C)2008,JPO&INPIT |
