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LM358 is a dual-operational amplifier with a wide range of applications. It has the advantages of a low price and a wide voltage range. A single-power-to-dual-current circuit composed of LM358 The single-power-to-dual-current circuit composed of operational amplifiers is shown in the figure below, which can convert 40V DC voltage into ±15V DC voltage. When the load current is 200mA, the voltage stability is not less than 0.1%. The circuit consists of a voltage divider, a voltage follower, and a shunt regulator. R1, Rw, and R3 form a voltage divider, which divides the 40V DC, take it out from the Rw boom and sends it to the non-inverting input of the op-amp. Since the inverting input terminal of the operational amplifier is connected to the ground wire, the operational amplifier forms a voltage follower circuit through the b-e junction of VT1 and VT2. VT1 and VT2 are -15V and +15V voltage regulator tubes respectively. The voltage drop generated by the op-amp output on R3 is used as the emitter junction bias voltage of VT1 and VT2 so that VT1 and VT2 are in the conduction state, and the positive and negative voltage of the output can be adjusted by adjusting the boom of RW. When using this circuit, the input DC power supply must be suspended, that is, neither end can be grounded. If there are any problems , feel free to ponint out.
