A circuit comprises a first supply line and a second supply line. A capacitor is arranged between the first supply line and the second supply line. The first supply line and the second supply line are inductively coupled, such that a switching current on the second supply line induces a compensating current into the first supply line. The compensating current compensates the switching current by flowing from the second supply line over the capacitor into the first supply line.
1. A circuit comprising:
a first supply line for supplying a first voltage;
a second supply line for supplying a second voltage;
a switch for switching a signal voltage on a signal line between the first voltage and the second voltage; and
a capacitor arranged between the first supply line and the second supply line;
wherein the first supply line and the second supply line are inductively coupled, such that a switching current on the second supply line induces a compensating current into the first supply line; and
wherein the compensating current compensates the switching current by flowing from the second supply line over the capacitor into the first supply line.
2. The circuit according to claim 1 , wherein the switch for switching is an output stage of a circuit chip.
3. The circuit according to claim 1 , wherein the switch for switching comprises a first transistor and a second transistor, wherein the first transistor connects the first supply line and the signal line, and wherein the second transistor connects the signal line and the second supply line.
4. The circuit according to claim 2 , wherein the capacitor is an in-chip power supply decoupling circuitry of the circuit chip.
5. The circuit according to claim 1 , wherein the signal line is connected to the first supply line via a resistor.
6. The circuit according to claim 1 , wherein the first supply line and the second supply line are connected to a provider for providing the first voltage and the second voltage to the first supply line and the second supply line.
7. The circuit according to claim 1 , further comprising a coupling region in which the first supply line and the second supply line are routed in parallel such that the switching current on the second supply line induces the compensating current into the first supply line.
8. The circuit according to claim 1 wherein the first supply line and the second supply line are printed circuit board traces or wires of a TSSOP like package.
9. The circuit according to claim 2 , wherein the circuit chip is a mommy chip which is arranged on a circuit package board and wherein the first supply line and the second supply line connect the memory chip to terminals of the circuit package board.