Fault protection in switch driver units
A device comprising a plurality of switches and a plurality of driver units. Each driver unit is coupled to drive a respective switch of the plurality of switches. A system controller is coupled to each of the driver units by a bus, wherein the system controller is configured to coordinate driving of the respective switches by the driver units. The device further comprises at least one communication channel coupled to each of the driver units, wherein the driver units are configured to communicate with each other over the communication channel without mediation by the system controller.
1 . A driver unit suitable for driving a transistor, the driver unit comprising:
a communications interface configured to receive timing information from a system controller indicating when the transistor driven by the driver unit is to be switched;
sense circuitry configured to sense one or more characteristics of a state of the transistor driven by the driver unit; and
fault protection control circuitry coupled to the sense circuitry and, based on the one or more characteristics of the state of the driven transistor, configured to categorize a fault in a driving of the driven transistor, wherein the fault protection control circuitry is coupled to output a categorization of the fault from the driver unit and wherein the fault protection control circuitry is further configured to interpret and respond to corresponding categorizations of faults in driving of other transistors by other driver units without mediation by the system controller.
2 . The driver unit of claim 1 , wherein the fault protection control circuitry is coupled to output the categorization of the fault from the driver unit via a terminal and to receive the corresponding categorizations via the same terminal.
3 . The driver unit of claim 1 , wherein the driver unit includes a first terminal and a second terminal both coupled to the system controller, wherein the first terminal is configured to receive the timing information and the second terminal is configured to receive position information that characterizes a position of the driver unit in a network of driver units, and wherein the timing of the driving of transistors by the driver units in the network is coordinated by the system controller.
4 . A driver module comprising:
a first switch and a second switch;
a control block configured to control the first switch and the second switch; and
an error flag interface block coupled to the control block and comprising a single terminal error flag input/output (EF I/O);
wherein the error flag interface block is configured to detect an external fault condition to the driver module indicated by an error flag state on the single terminal EF I/O, wherein the external fault condition is detected outside the driver module,
wherein the control block is coupled to inhibit the switching of the first switch and the second switch in response to the detection of the external fault condition, and
wherein the error flag interface block is configured to set the error flag state on the single terminal EF I/O responsive to the detection of a local fault condition in the driver module by the control block.
5 . The driver module of claim 4 , wherein the local fault condition is selected from the group consisting of over-current, over-voltage, and over-temperature.
6 . The driver module of claim 4 , wherein the error flag interface block is coupled to respond to a reset state on the single terminal EF I/O and coupled to the control block to allow the switching of the first switch and the second switch.
7 . The driver module of claim 4 , wherein the driver module is a half-bridge inverter.
8 . The driver module of claim 4 , wherein the first switch, the second switch, the control block and the error flag interface block are in a single package.