Power supply device, AC adapter, AC charger, electronic device, and power supply system

A power delivery device comprising:

• a DC/DC converter disposed between an input and an output;
• a primary-side controller configured to control an input current of the DC/DC converter;
• and
• an insulation circuit connected to a control input terminal, the insulation circuit configured to feedback a control input signal to be supplied to the control input to the primary-side controller from an external apparatus to which electric power is delivered, wherein:
• the control input terminal comprises a front-side terminal electrode and a back-side terminal electrode so as to be connectable from the external apparatus without distinction between front and back sides;
• and
• the primary-side controller varies an output voltage value and an available output current capacity of the DC/DC converter by controlling the input current of the DC/DC converter on the basis of the control input signal fed back from the insulation circuit.

A power delivery device comprising:

• a DC/DC converter disposed between an input and an output;
• a primary-side controller configured to control an input current of the DC/DC converter;
• an insulation circuit connected to a control input, the insulation circuit configured to feed back a control input signal of the control input to the primary-side controller;
• an AC coupling capacitor coupled to the control input;
• a switch connected to an output of the DC/DC converter, the switch configured to interrupt the output voltage of the DC/DC converter;
• a power source supply circuit connected between the input and the primary-side controller, the power source supply circuit configured to supply a power source to the primary-side controller;
• and
• an AC/DC converter connected between an AC input and an input of the DC/DC converter, wherein
• the primary-side controller varies an output voltage value and an available output current capacity of the DC/DC converter by controlling the input current on the basis of the control input signal fed back from the insulation circuit, wherein
• the insulation circuit is connected to the control input through the AC coupling capacitor, and the AC coupling capacitor is contained in the insulation circuit, wherein
• the switch comprises an insulated gate field effect transistor, and the DC/DC converter comprises a diode rectification, wherein
• the DC/DC converter comprises:
• a transformer;
• a first MOS transistor and a current sensing resistor connected in series between a primary-side inductance of the transformer, and a ground potential;
• a diode connected between a secondary-side inductance of the transformer, and the output;
• and
• a first capacitor connected between the output and the ground potential.

A power delivery system comprising a power delivery device, the power delivery device comprising:

• a DC/DC converter disposed between an input and an output;
• a primary-side controller configured to control an input current of the DC/DC converter;
• and
• a secondary-side controller coupled to a control input terminal, the secondary-side controller configured to receive a control input signal to be supplied to the control input from an external apparatus to which electric power is delivered, and then feedback the received control input signal to the primary-side controller, wherein:
• the control input terminal comprises a front-side terminal electrode and a back-side terminal electrode so as to be connectable from the external apparatus without distinction between front and back sides;
• and
• the primary-side controller varies an output voltage value and an available output current capacity of the DC/DC converter by controlling the input current of the DC/DC converter on the basis of the control input signal fed back from the secondary-side controller.