In some embodiments, a near-field sensor comprises an antenna system, transmit circuitry configured to transmit pulses via the antenna system, and receive circuitry configured to receive interrogation signals in response to transmitted pulses. The antenna system can include a first conductive path having one or more loops coupled together, and a second conductive path having one or more loops coupled together, wherein the first and second conductive path are electrically isolated from each other within the antenna system. The transmit circuitry can include a matching network to dissipate energy stored in the transmit circuitry following transmission of a pulse. The receive circuitry can include a suppression network configured to dissipate residual energy within the receive circuitry resulting from transmission of the pulse.

An electronic device can include a battery bus, a load having a transient power requirement, and a transient power management circuit coupled between the battery bus and the load and configured to meet the transient instantaneous power requirement of the load while maintaining a minimum voltage on the battery bus. The transient power management circuit can include a boost converter coupled between the battery bus and a capacitor bank, and the load may be coupled to the capacitor bank. A control circuit may be configured to operate the boost converter to charge the capacitor bank. A control switch may be coupled between the boost converter and the capacitor bank, and the control circuit may be further configured to limit inrush current into the capacitor bank. Additionally, a state of charge of the battery may be estimated from a time required to charge the capacitor bank.

A transient noise reduction filter comprises a cable including one or more twisted pairs of conductors and one or more common mode chokes (CMCs). The one or more CMCs a formed from respective pluralities of turns of the cable. Each of the CMCs may be a magnetic CMC wherein the plurality of turns of the cable are wrapped around a magnetic core, or an air-core CMC wherein the plurality of turns of the cable are not wrapped around a magnetic core but are instead disposed around a non-magnetic material (such as air)

A system includes a first transistor having a first control input and first and second current terminals. The first current terminal couples to an input voltage node. A second transistor has a second control input and third and fourth current terminals. The third current terminal couples to the second current terminal at a first node. The fourth current terminal couples to an output voltage node. A drive circuit is configured to charge a capacitor maintain the first transistor in an off state responsive to a negative voltage on the input voltage node, and, responsive to a negative voltage on the input voltage node, to cause the charge from the capacitor to be used to turn off the first transistor. The system provides a voltage to a load coupled to the output voltage node.

A drive for a mobile compressor includes EMI and transient protection circuits, second chokes, converters and an inverter. The EMI and transient protection circuits include respectively common mode chokes and at least one component. Each of the common mode chokes is configured to receive a first direct current voltage and is connected to first and second grounds. The at least one component is connected to a third ground. The first, second and third grounds are at different voltage potentials. The second chokes are connected downstream from the common mode chokes. The converters are connected to outputs of the second chokes and are configured to collectively provide a second direct current voltage to a direct current bus. The inverter is connected to the direct current bus and configured to convert the second direct current voltage to an alternating current voltage to power the mobile compressor downstream from the inverter.

The present disclosure provides an electrostatic discharge protection circuit, a chip including a first pad and a second pad. The electrostatic discharge protection circuit includes a trigger unit and a discharge transistor. The trigger unit is connected between the first pad and the second pad, provided with a trigger terminal, and configured to generate a trigger signal when there is an electrostatic pulse on the first pad. The first pad is connected to a first voltage, the second pad is connected to a second voltage, and the first voltage is greater than the second voltage. The discharge transistor has a first terminal connected to the first pad, and a second terminal connected to the second pad, and discharges an electrostatic charge to the second pad when triggered by the trigger signal.

Disclosed herein are embodiments of a scalable connection and disconnection differential surge limiter circuit that may be utilized in any AC-coupled transceiver. Charge is recycled between PADP and PADN using two diode paths, hence protecting the PAD connected devices from voltage stress. The circuit can act as a protection circuit to limit the voltage on PADP and PADN during differential voltage spikes.

An overvoltage recovery circuit (ORC), a controller for an HVAC system and an HVAC system are disclosed herein. In one embodiment, the ORC includes: (1) a first supply voltage terminal connected to a first voltage supply, (2) a second supply voltage terminal connected to a second voltage supply, (3) interruption circuitry including a switch and a trip terminal connected to the second supply voltage terminal and (4) detection circuitry connected to the first supply voltage terminal and the switch of the interruption circuitry, the detection circuitry configured to operate the switch in response to an overvoltage condition at the first supply voltage terminal.

A protection circuit, comprising: a transient suppression circuit, configured to suppress a transient voltage; and a short-circuit protection circuit connected between the transient suppression circuit and a ground terminal, wherein when the transient suppression circuit is shorted out and the transient voltage is a protection voltage, the short-circuit protection circuit disconnects a loop where the transient suppression circuit is located. The short-circuit protection circuit has a turned-on state and a turned-off state; the short-circuit protection circuit is in a turned-on state when the transient suppression circuit is shorted out and the transient voltage is greater than the protection voltage; and the short-circuit protection circuit is in a turned-off state when the transient suppression circuit is shorted out and the transient voltage is a protection voltage.

The present disclosure provides a power clamp device. The power clamp device includes a delay element, a first transistor, a second transistor, and a gate control circuit. The delay element has an input terminal and an output terminal. The first transistor has a gate electrically connected to the output terminal of the delay element. The second transistor has a source electrically connected to a drain of the first transistor. The gate control circuit has a first terminal electrically connected to the input terminal of the delay element, a second terminal electrically connected to the output terminal of the delay element, and a third terminal electrically connected to a gate of the second transistor.