| 摘要 |
PURPOSE:To obtain a base current compensation circuit that has no interference to an active part with low cost by using the base current of an adverse conduction type transistor to compensate the base current without having the cascade structure of an active system. CONSTITUTION:The base current is set at I0/hFE(Q106) for a transistor (TR)106 of an active system for compensation of the base current since the working current value I0 is decided by a constant current source 107. While a TR forming a compensation circuit is provided together with constant current sources 101-104. The base current of a TR102 is set at I0XhFE(Q101)/ hFE(Q103).hFE(Q102) since the emitter current of a TR103 is set at the same level as that of the current source 107 by a constant current source 104. Then the base currents of both TRs 102 and 105 have the same absolute value and opposite polarities and therefore can easily be compensated as long as hFE(Q101)= hFE(Q102) and hFE(Q103)=hFE(Q105) are satisfied.
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