| 摘要 |
PURPOSE:To make it possible to divide electric currents with required weight accurately by using a small number of active elements while causing a few errors, by leading constant electric currents of a value, obtained by dividing constant electric current, out of respective collectors of subordinate electric current source transistors. CONSTITUTION:To division terminals 12-16 of resistance network 2 that divide constant electric current with weight, emitters of current source transistors 67-71 are connected. Those transistors 67-71 are provided with compensating transistors 72-76 to compensate their base currents and from respective collectors of base compensating transistors 72-76 and current source transistors 67-71, weight currents are led out. To hold respective division terminals of resistance network 2 at constant potentials, emitter areas of current source and compensating transistors 67- 71, and 72-76 are selected in area proportion that corresponds to each area. Thus, respective current source transistors 67-71 are reduced sufficiently in error due to their base currents and the number of elements can be reduced remarkably. |
