| 摘要 |
<p>PURPOSE:To obtain a stable operating characteristic which is not influenced by the variation in case of a manufacture by constituting a device so that a full- wave rectifying circuit in an extracting part of a timing signal of a bipolar code transmission signal is formed as an LSI circuit which can be manufactured by a CMOS process. CONSTITUTION:An input signal VIN is inverted against a reference voltage VR by an operational amplifier OP1. Three transistors TB1, TB2 and TB3 become a load of a current source transistor Tc, and the collectors and the emitters are connected in parallel to a power source VDD and the drain of the transistor Tc, respectively. An emitter voltage VE which is common to each transistor becomes a value which is lower by a base - emitter voltage VBE of the trnasistor than the maximum voltage in the base voltage of each transistor. This voltage VE is amplified by the operational amplifier, and inputted to a tank circuit 12 as an output of a full-wave rectifying circuit 11. A slice level voltage VX is set to an intermediate value (50% of O - peak of a signal) of the reference voltage VR and a peak voltage VP of an input signal.</p> |
