Digital Frequency Divider, Voltage Supply, and Method for Operating and Testing a Voltage Supply

A controller of a vehicle, comprising:

• a connection for a voltage supply circuit,
• an output for a clock signal at a predetermined frequency, f0, for a digital frequency divider;
• wherein the controller is designed to control the digital frequency divider,
• wherein the digital frequency divider comprises:
• a counting unit which has a clock input for the clock signal, a reset input for a reset signal, and a plurality of outputs for division signals, the counting unit being configured to generate the division signals as a division of the clock signal by a power of 2;
• a first coupling circuit for coupling the division signals to form a coupling signal, wherein the coupling signal has a logical HIGH only when all coupled division signals have a logical HIGH;
• and
• a second coupling circuit which is designed to enter the coupling signal into the reset input of the counting unit;
• and
• wherein the voltage supply circuit comprises:
• a power management system for providing a voltage for the controller,
• wherein the digital frequency divider is configured to receive the clock signal from the controller and to divide the received clock signal in a predetermined division ratio and to provide an output to the power management system.

A method for operating and testing a voltage supply circuit, comprising:

• providing a voltage for a vehicle controller;
• transmitting, by way of the vehicle controller, a clock signal at a predetermined frequency f0;
• dividing the frequency f0 of the clock signal by a non-binary division ratio;
• and
• authenticating the vehicle controller when the divided frequency is in a predetermined acceptance window.