The present invention provides a current detection circuit applied to a SiC field effect transistor. The current detection circuit includes a current detection loop and an acquisition loop on the current detection loop. The current detection loop includes a voltage source, a capacitor, a first SiC field effect transistor, a second SiC field effect transistor, and a sampling resistor. The first SiC field effect transistor is connected to a power signal. The second SiC field effect transistor is connected to a pulse signal. The acquisition loop includes a compensating resistor and a compensating inductor. The compensating resistor and the compensating inductor are connected in series and then connected in parallel at two ends of the sampling resistor to counteract the influence of total parasitic inductance in the current detection loop.

An open circuit diagnosis apparatus, and method for open circuit diagnosis, for a motor drive circuit with a Miller plateau detection unit that detects whether there is a Miller plateau region in a gate voltage applied to a switching element of a motor drive circuit when the switching element is turned on; a body diode activation detection unit which detects whether the body diode of the switching element has been activated which depends on the on/off state of the switching element; and a control unit which determines whether the motor drive circuit is in the open circuit state on the basis of whether the body diode activation unit has been activated and whether there is a Miller plateau region in a gate voltage.

HVAC components having improved efficiency are described. In one embodiment, excessive sleep current draw in a battery-powered device having a microcontroller is detected by measuring a voltage drop across a MOSFET device coupled in a forward-conducting orientation in series between the battery and the microcontroller, causing a transistor to conduct when the voltage drop exceeds a predetermined threshold to generate a first trigger signal, integrating the first trigger signal to generate a second trigger signal, and generating an interrupt to the microcontroller. In another embodiment, a battery-saving method of operating an HVAC component includes maintaining the HVAC device in the sleep mode, receiving a user input to wake the device, transmitting a data request and returning the HVAC component to the sleep mode, waking up the HVAC device to poll an adjacent network node storing a cached response, displaying the response, and returning the HVAC device to sleep.

An integrated circuit includes an H-bridge circuit having a first output node for coupling to a high-side terminal of an inductor and a second output node for coupling to a low-side terminal of the inductor. A current sense FET is coupled between a current source and the lower supply voltage to provide a reference current that includes a peak current limit at a sensing node. A current-sense comparator has a first input coupled to the sensing node, a second input coupled to the second output node and an output coupled to send an output signal towards a driver control circuit. A FET linear detection circuit is coupled to receive a gate voltage of an active low-side power FET and has an output coupled to enable the current-sense comparator when the active low-side power FET is operating in a linear region.

A device for detecting the polarity of a current or voltage, the detection device including a circuit portion with a detection node configured to produce at the detection node a measurement voltage which is an image of a fraction of the detected current or voltage, and a detection circuit with transistor(s), coupled to the detection node, and provided with amplifier(s), with a comparator transistor having a source gate voltage which depends on the measurement voltage. The comparator transistor further includes a source set at a first fixed potential and a source-gate voltage which depends on the measurement voltage or a gate set at a second fixed potential and a source-gate voltage which depends on the measurement voltage, the detection circuit being configured to compare the measurement potential with a threshold and to output a binary detection signal indicating the polarity of the detected current or voltage.

A detection circuit is used to detect an input current of a switching power conversion circuit. The current detection circuit includes a current transform unit, a first unidirectional conduction component assembly, a flux reset circuit, a second unidirectional conduction component assembly, a first switch, a second switch, a control unit, and a detection unit. The current transform unit is coupled to a power switch of the switching power conversion circuit, and the first unidirectional conduction component assembly, the flux reset circuit, and the second unidirectional conduction component assembly are connected in parallel to the current transform unit. The first switch and the second switch are coupled to the first or second unidirectional conduction component assembly, and the control unit correspondingly controls the first switch and the second switch according to a first or second direction voltage of the input voltage.

In various embodiments, a current measurement circuit measures an input current within an integrated circuit. The current measurement circuit includes an integration capacitor, an operational amplifier, a comparison capacitor, an inverter, and multiple switches. The current measurement circuit is coupled to a clocking circuit that, during operation, generates a two-phase clock having a frequency that is proportional to the input current. At least a portion of the switches are turned on during a first phase of the two-phase clock and are turned off during a second phase of the two-phase clock.

HVAC components having improved efficiency are described. In one embodiment, excessive sleep current draw in a battery-powered device having a microcontroller is detected by measuring a voltage drop across a MOSFET device coupled in a forward-conducting orientation in series between the battery and the microcontroller, causing a transistor to conduct when the voltage drop exceeds a predetermined threshold to generate a first trigger signal, integrating the first trigger signal to generate a second trigger signal, and generating an interrupt to the microcontroller. In another embodiment, a battery-saving method of operating an HVAC component includes maintaining the HVAC device in the sleep mode, receiving a user input to wake the device, transmitting a data request and returning the HVAC component to the sleep mode, waking up the HVAC device to poll an adjacent network node storing a cached response, displaying the response, and returning the HVAC device to sleep.

A device includes a current mirror, a switch, first and second current paths, first and second buffers, a variable resistor, a temperature-sensing circuit, and a controller. The first current path is coupled between the current mirror's input and the switch. The switch switches between ground and a transistor based on a control signal. The second current path is coupled between a first current mirror output and ground. The first buffer is coupled to a second current mirror output. The second buffer is coupled to the variable resistor, which is coupled to the first buffer. The temperature-sensing circuit provides a device temperature to the controller, which is coupled to a first buffer output and determines a first adjustment to the first and second current paths and a second adjustment to the variable resistor based on the device temperature.

A circuit and method for detecting a failure of a switching power device is disclosed. The circuit and method utilize a Kelvin connection of a four-terminal configuration of the switching power device to sense a resistance of at least one wire-bond. The resistance corresponds to a defect or defects in the at least one wire-bond and so it can be used to detect a failure before damage occurs. A threshold used for detecting the failure can be adjusted to accommodate variations in the switching power device and/or the application in which it is being used. Additionally, the failure detection is carried out at a period after the switching power device is turned ON to prevent switching transients from affecting the detection.