Method and device to operate a power switch in multiple modes

A bi-directional switched mode power supply (SMPS) comprising:

• a first terminal and a second terminal providing external connections for the SMPS;
• a high-side switch and a low-side switch coupled together at a switching node, the high-side switch coupled to the first terminal, each of the high-side switch and the low-side switch comprising an intrinsic diode configured to conduct current in a reverse direction of the high-side switch and the low-side switch;
• an inductor electrically interposed between the switching node and the second terminal;
• a controller configured to generate a switch control signal for controlling a switching of the high-side switch and/or the low-side switch;
• a first driver control circuit configured to control a conductivity of the high-side switch based on a sensed current and/or voltage at the high-side switch responsive to receiving a first switching mode indication, and to control the conductivity of the high-side switch based on the switch control signal generated by the controller responsive to receiving a second switching mode indication;
• and
• a second driver control circuit configured to control a conductivity of the low-side switch based on a sensed current and/or voltage at the low-side switch responsive to receiving the first switching mode indication, and to control the conductivity of the low-side switch based on the switch control signal generated by the controller responsive to receiving the second switching mode indication,
• wherein the SMPS is configured to operate, during a first interval, in a first mode, in which power is transferred from the first terminal to the second terminal, and, during a second interval, in a second mode, in which power is transferred from the second terminal to the first terminal.

A bi-directional DC/DC converter comprising:

• a first direct-current (DC) power node for connecting to a first power source or sink;
• a second DC power node for connecting to a second power source or sink;
• an isolation transformer comprising a primary winding and a secondary winding;
• a primary-side power stage configured to couple the first DC power node to the primary winding;
• a secondary-side power stage configured to couple the secondary winding to the second DC power node and comprising:
• a secondary-side half bridge including first and second secondary-side power switches arranged in a half-bridge configuration;
• and
• first and second secondary-side switch controller circuits coupled, respectively, to the first and second secondary-side power switches, each of the first and second secondary-side switch controller circuits configured for operation in a first mode, in which a conductivity of the respective one of the first and second secondary-side power switches coupled to the respective one of the first and second secondary-side switch controllers is based on a sensed current and/or voltage at the respective power switch, and in a second mode, in which an externally-provided switch control signal controls the conductivity of the respective one of the first and second secondary-side power switches coupled to the respective one of the first and second secondary-side switch controller circuits;
• a controller configured to operate the bi-directional DC/DC converter, during a first interval, in a forward mode, in which power is transferred from the first DC power node to the second DC power node, and, during a second interval, in a reverse mode, in which power is transferred from the second DC power node to the first DC power node;
• wherein, for the forward mode, the controller is configured to set the first and second secondary-side controller circuits to operate the first and second secondary-side power switches in the first mode, and
• wherein, for the reverse mode, the controller is configured to generate the externally-provided control signal for the first and second secondary-side power switches.