Charger control circuit and method for charger control

A method for charger control in a portable electronic device, comprising

• assigning a voltage applied at a first charger terminal of a charger control circuit to one of at least three voltage ranges by performing at least one voltage comparison, wherein a first voltage range of the at least three voltage ranges corresponds to voltage values below a first threshold value, a second voltage range of the at least three voltage ranges corresponds to voltage values above the first threshold value and below a second threshold value, and a third voltage range of the at least three voltage ranges corresponds to voltage values above the second threshold value, wherein the second threshold value is greater than the first threshold value;
• determining and distinguishing, based on the assignment, whether an external charger or a secondary battery is connected to the first charger terminal;
• and
• depending on a predetermined operating state of the first charger terminal
• supplying power from the secondary battery to the portable electronic device via a system terminal of the charger control circuit when the secondary battery is connected to the first charger terminal;
• and
• supplying power from the external charger to the portable electronic device via the system terminal when the external charger is connected to the first charger terminal.

A charger control circuit for a portable electronic device, the charger control circuit comprising:

• a first charger terminal,
• a first comparator having a first input connected to the first charger terminal and a second input to which a first threshold value is applied, and
• a second comparator having a first input connected to the first charger terminal and a second input to which a second threshold value is applied,
• wherein the charger control circuit is configured to assign a voltage applied at the first charger terminal to one of at least three voltage ranges by using a first comparator signal of the first comparator and a second comparator signal of the second comparator, wherein a first voltage range of the at least three voltage ranges corresponds to voltage values below the first threshold value, a second voltage range of the at least three voltage ranges corresponds to voltage values above the first threshold value and below the second threshold value, and a third voltage range of the at least three voltage ranges corresponds to voltage values above the second threshold value, wherein the second threshold value is greater than the first threshold value.