Infineon Technologies Ag

Michael Krug

Marco Bachhuber

Marcus Nuebling

Tommaso Bacigalupo

Tomas Manuel Reiter

Matthias Weinmann

Jens Barrenscheen

Felix Weidner

Christian Walther

Benedikt Hanelt

This disclosure is directed to a driver circuit configured to control a power switch. The driver circuit may comprise an output pin, wherein the driver circuit is configured to deliver drive signals from the output pin to the power switch to control turn ON of the power switch; a multi-function pin; and a state machine configured to define operation of the driver circuit using the multi-function pin, wherein the state machine is configured to select among a soft turn OFF mode, a clamping mode, and an in-line characterization mode.

Driver circuit with a multi-function pin used for in-line characterization of a power switch

A gate driver circuit includes one or more datastores configured to store one or more result registers, timer circuitry configured to generate a timing signal, and logic circuitry. The logic circuitry is configured to drive switching circuitry using a switching signal and determine a triggering point of a first cycle of the switching signal. In response to the determination of the triggering point, the logic circuitry is configured to control, using the switching signal, one or more analog-to-digital converters (ADCs) to store a first data sample at the one or more result registers. In response to a determination that the switching signal does not include a triggering point, the logic circuitry is configured to control, using the timing signal, the one or more ADCs to store a second data sample at the one or more result registers.

Gate driver circuit for sampling without a triggering point

A circuit includes one or more datastores configured to store a result register and a readout counter value and logic circuitry coupled to the one or more datastores. The logic circuitry is configured to cause, for a cycle of a plurality of cycles of a periodic signal, one or more analog-to-digital converters (ADCs) to store data to the result register and modify the readout counter value in response to the one or more ADCs storing the data to the result register for the cycle. In response to a read request for the data at the result register for the cycle, the logic circuitry is configured to output the data stored by the result register, output the readout counter value for the cycle, and, after the output of the readout counter value, set the readout counter value to a predetermined value.

Result register with readout counter value

Overload detection and protection for power switch circuits. For circuits with faster switching speed, fast fault detection and response to a detected overload condition may be desirable. Detection circuitry may monitor a voltage on the control terminal of one or more power switches. Based on empirical measurements, in an overload condition of a power switch circuit, e.g., a half-bridge circuit, the voltage at the control terminal may increase, and in some examples, increase to a magnitude that is greater than a supply voltage. A comparator may detect a voltage increase that exceeds a voltage magnitude threshold, output an indication to control circuitry for the power switch circuit, and the control circuitry may take action to protect the rest of the circuitry, such as reduce voltage or shut off the power switch circuit.

Diagnosis of gate voltage to detect high current

A method may comprise: controlling ON/OFF switching of a power switch via a driver circuit; receiving a first signal on a detection pin associated with the power switch, wherein the first signal corresponds to a first point in time when current is not passing through the power switch and wherein the first signal indicates a first voltage drop over one or more other circuit elements; receiving a second signal on the detection pin, wherein the second signal, wherein the second signal corresponds to a second point in time when current is passing through the power switch and wherein the second signal indicates a voltage drop over the power elements; and determining the voltage drop over the power switch based on a difference between the first signal and the second signal.

Techniques for measuring voltage over a power switch using zero current detection point

This disclosure describes circuits and techniques for identifying potential problems with control signals for power switches. More specifically, this disclosure describes the use of registers, e.g., volatile or non-volatile storage elements, configured to count the rising and/or falling edges of pulse modulation (PM) signals within driver circuits or other control circuits. By counting the edges of PM signals within driver circuits, signaling problems can be identified based on mismatch between different counters. The techniques may be used by a driver circuit to detect circuit problems, or readout of the registers can be done after device failure, in order to help identify whether signaling problems may have caused the device failure.

Pulse counting registers for monitoring control signals of power switches

A driver may comprise a first node, a second node, and processing circuitry. The first node is configured to receive a command from controller circuitry. The second node is configured to receive a commutation signal for activating or deactivating a switch. The processing circuitry is configured to determine, based on the received command, an activation setting for an activation characteristic for the switch and a deactivation setting for a deactivation characteristic for the switch and drive the switch based on the commutation signal. To drive the switch, the processing circuitry is configured to change, at a first time, the deactivation characteristic for the switch from a previous deactivation setting to the determined deactivation setting and change, at a second time that is different from the first time, the activation characteristic for the switch from a previous activation setting to the determined activation setting.

Scheduling commutation behavior changes for a driver

A driver circuit is configured to control a power transistor. The driver circuit comprises a signal generator configured to generate a control signal for the power transistor based on a supply signal and an input signal from a control unit. In addition, the driver circuit includes a ripple detector configured to receive the supply signal and determine whether the supply signal includes a ripple error. In some examples, the ripple detector may be configured to send a warning signal to the control unit in response to detecting the ripple error.

Ripple detector for monitoring a supply to galvanically isolated gate driver

A driver circuit is configured to deliver drive signals from an output pin to a power switch to control ON/OFF switching of the power switch. A first detection pin of the driver circuit is configured to receive a first signal associated with the power switch, wherein the first signal indicates a voltage drop over the power switch and a voltage drop over one or more other circuit elements. A second detection pin is configured to receive a second signal, wherein the second signal indicates a voltage drop over one or more matched circuit elements, wherein the one or more matched circuit elements associated with the second signal are substantially identical to the one or more other circuit elements associated with the first signal. The driver circuit is configured to determine the voltage drop over the power switch based on a difference between the first signal and the second signal.

Differential techniques for measuring voltage over a power switch

A device configured to monitor a voltage at a voltage rail for driving a motor includes processing circuitry configured to receive an indication of a switching signal for a phase of a plurality of phases of the motor. Inverter circuitry associated with the device is configured to electrically couple the phase to the voltage rail or to a reference rail associated with the voltage rail based on a driving signal that is generated based on the switching signal. The processing circuitry is further configured to determine a measurement time to measure the voltage at the voltage rail based on the switching signal and generate, using an analog-to-digital converter (ADC), a set of measured voltage values based on the voltage at the voltage rail during the measurement time.

Voltage monitor using switching signal for motor

This disclosure is directed to circuits and techniques for protecting a power switch when the power switch is turned ON. A driver circuit may detect whether the power switch is in a desaturation mode or an overcurrent state based on a signal at a detection pin, and disable the power switch in response to detecting that the power switch is in the desaturation mode or the overcurrent state. In addition, the driver circuit may detect whether the power switch is trending towards a safe operating area (SOA) limit of the power switch based on a rate of change of the signal, and disable the power switch in response to detecting that the power switch is trending towards the SOA limit.

Monitoring safe operating area (SAO) of a power switch

This disclosure is directed to circuits and techniques for protecting a body diode of a power switch from an inductive load when the power switch is turned OFF. A driver circuit may detect whether the power switch is in a desaturation mode when the power switch is turned ON and disable the power switch in response to detecting that the power switch is in the desaturation mode. In addition, the driver circuit may detect whether the body diode of the power switch needs protection when the power switch is turned OFF, and in response to detecting that the body diode needs protection, control the power switch according to a body diode protection scheme.

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Munich, Germany

Michael Krug