An oscillator circuit, comprising: an amplifier circuit including: a first amplifier including a first input coupled with a bias node, a second input coupled with a first node, and a first amplifier output adapted to provide a first amplifier output signal (VOTA1); and a resistance coupled between the first node and the first amplifier output; an integrator circuit including: a second amplifier including a first input coupled with the bias node, a second input coupled with a second node, and a second amplifier output adapted to provide a second amplifier output signal (VOTA2); and a capacitance coupled between the second node and the second amplifier output; a comparator including: a first comparator input coupled with the first amplifier output to receive the first amplifier output signal (VOTA1), a second comparator input coupled with the second amplifier output to receive the second amplifier output signal (VOTA2), and a comparator output adapted to provide an oscillator output signal (VOUT) alternating between a first level and a different second level; a first current source adapted to provide a first current signal of a first current value to the first node; a second current source adapted to provide a second current signal of the first current value to the second node; a third current source adapted to provide a third current signal of twice the first current value from a third node to a constant voltage node; a fourth current source adapted to provide a fourth current signal of twice the first current value from a fourth node to the constant voltage node; and a switching circuit operative according to the oscillator output signal (VOUT) to disconnect the third node from the first node and to disconnect the fourth node from the second node when the oscillator output signal (VOUT) is at the first level, and to couple the third node with the first node and to couple the fourth node with the second node when the oscillator output signal (VOUT) is at the second level. an amplifier circuit including: a first amplifier including a first input coupled with a bias node, a second input coupled with a first node, and a first amplifier output adapted to provide a first amplifier output signal (VOTA1); and a resistance coupled between the first node and the first amplifier output; an integrator circuit including: a second amplifier including a first input coupled with the bias node, a second input coupled with a second node, and a second amplifier output adapted to provide a second amplifier output signal (VOTA2); and a capacitance coupled between the second node and the second amplifier output; a comparator including: a first comparator input coupled with the first amplifier output to receive the first amplifier output signal (VOTA1), a second comparator input coupled with the second amplifier output to receive the second amplifier output signal (VOTA2), and a comparator output adapted to provide an oscillator output signal (VOUT) alternating between a first level and a different second level; a first current source adapted to provide a first current signal of a first current value to the first node; a second current source adapted to provide a second current signal of the first current value to the second node; a third current source adapted to provide a third current signal of twice the first current value from a third node to a constant voltage node; a fourth current source adapted to provide a fourth current signal of twice the first current value from a fourth node to the constant voltage node; and a switching circuit operative according to the oscillator output signal (VOUT) to disconnect the third node from the first node and to disconnect the fourth node from the second node when the oscillator output signal (VOUT) is at the first level, and to couple the third node with the first node and to couple the fourth node with the second node when the oscillator output signal (VOUT) is at the second level.