| 摘要 |
PURPOSE:To generate two high-precision DC voltages independent of each other and reduce the circuit scale by making it possible that DC voltages set to values independent of each other are generated with one stabilized power source and a series connection resistance group. CONSTITUTION:A stabilized power source 11 outputs a stabilized voltage 101. The voltage 101 and a negative feedback voltage 106 are supplied to a DC amplifier 21, and the amplifier 21 outputs a DC reference voltage 102. A negative feedback circuit 23 consists of plural switching elements, and plural DC voltages 105 obtained by dividing the voltage 102 by a series connection resistance group 22 are supplied to one ends of these switching elements. The other ends of these switching elements are connected to the negative feedback voltage input terminal of the amplifier 21. Only one of plural switching elements is made conductive to output one of voltages 105 as a voltage 106. An adjusting circuit 24 receives plural voltages 104, which are a part of plural DC voltages of the resistance group 22, and selects fixedly one DC voltage of them and outputs it as a reference voltage 107 to a terminal 26. |
