Differential current buffer circuit and dc and alternating current source comprising the same

A differential current buffer circuit comprising:

• a differential input stage that is powered from a first low-impedance positive supply voltage source and a first low-impedance negative supply voltage source, the differential input stage having
• a first input circuit whose outputs are connected between a first current path of a first output current mirror connected to a second low-impedance positive supply voltage source and a first current path of a second output current mirror connected to a second low-impedance negative supply voltage source, and
• a second input circuit whose outputs are connected between a first current path of a third output current mirror connected to the second low-impedance positive supply voltage source and a first current path of a fourth output current mirror connected to the second low-impedance negative supply voltage source,
• wherein, referred to a reference potential, a second low-impedance positive supply voltage from the second low-impedance positive supply voltage source is higher than a first low-impedance positive supply voltage from the first low-impedance positive supply voltage source and a second low-impedance negative supply voltage from the second low-impedance negative supply voltage source is lower than a first low-impedance negative supply voltage from the first low-impedance negative supply voltage source,
• wherein a first output of the differential current buffer circuit is tapped off between the respective second current paths of the first and second output current mirrors, and
• wherein a second output of the differential current buffer circuit is tapped off between the respective second current paths of the third and fourth output current mirrors.