A method and circuit for controlling current through an inductive load such as an electromagnetic valve of a vehicle anti-lock braking system includes first and second driver stages, controlled by PWM (pulse width modulation) signals, for providing, respectively, an actuation path for valve current in an on phase and a recirculation path for valve current in an off phase. A peak value of current flowing in the actuation path at the end of an on phase is compared with a peak value of current flowing in the recirculation path at the start of the off phase in order to detect any malfunction of the circuit. An embodiment of the invention has the advantage of being able to detect any malfunction at very low and very high PWM duty cycles.

A method and circuit for controlling current through an inductive load such as an electromagnetic valve of a vehicle anti-lock braking system includes first and second driver stages, controlled by PWM (pulse width modulation) signals, for providing, respectively, an actuation path for valve current in an on phase and a recirculation path for valve current in an off phase. A peak value of current flowing in the actuation path at the end of an on phase is compared with a peak value of current flowing in the recirculation path at the start of the off phase in order to detect any malfunction of the circuit. An embodiment of the invention has the advantage of being able to detect any malfunction at very low and very high PWM duty cycles.

According to a method herein, a multi-level inductor is created around a through-silicon-via (TSV) in a semiconductor substrate. A voltage induced in the multi-level inductor by current flowing in the TSV is sensed, using a computerized device. The voltage is compared to a reference voltage, using the computerized device. An electrical signature of the TSV is determined based on the comparing the voltage to the reference voltage, using the computerized device.

According to a method herein, a multi-level inductor is created around a through-silicon-via (TSV) in a semiconductor substrate. A voltage induced in the multi-level inductor by current flowing in the TSV is sensed, using a computerized device. The voltage is compared to a reference voltage, using the computerized device. An electrical signature of the TSV is determined based on the comparing the voltage to the reference voltage, using the computerized device.

An apparatus for providing security for an integrated circuit (IC) chip is disclosed. The apparatus may include the IC chip, attached to a surface of a printed circuit board (PCB). The PCB may include a first, electrically insulative, conformal coating layer attached to the PCB surface and to exposed IC chip surfaces. The PCB may also include a Wheatstone bridge circuit to indicate changes to a second, X-ray opaque, optically opaque and electrically resistive, conformal coating layer. The circuit may include four resistors, formed from second conformal coating layer regions, four sets of electrically conductive pads on the PCB, each set electrically connected to a resistor of the four resistors. The circuit may also include a voltage source, connected to two conductive pads and a monitoring device, connected to another two conductive pads and configured to detect a change of resistance of the Wheatstone bridge.

An apparatus for providing security for an integrated circuit (IC) chip is disclosed. The apparatus may include the IC chip, attached to a surface of a printed circuit board (PCB). The PCB may include a first, electrically insulative, conformal coating layer attached to the PCB surface and to exposed IC chip surfaces. The PCB may also include a Wheatstone bridge circuit to indicate changes to a second, X-ray opaque, optically opaque and electrically resistive, conformal coating layer. The circuit may include four resistors, formed from second conformal coating layer regions, four sets of electrically conductive pads on the PCB, each set electrically connected to a resistor of the four resistors. The circuit may also include a voltage source, connected to two conductive pads and a monitoring device, connected to another two conductive pads and configured to detect a change of resistance of the Wheatstone bridge.

A power-supply voltage sensing device is disclosed, which relates to a technology for detecting a level of an external power-supply voltage during a test mode. The power-supply voltage sensing device includes a reference voltage trimming unit configured to trim a reference voltage in response to a code signal, a power-supply voltage detection unit configured to select one of a power-supply voltage and an external power-supply voltage in response to a test signal, compare the external power-supply voltage with the reference voltage, and output a detection signal according to the result of comparison, and a reference voltage control unit configured to output the code signal in response to the detection signal.

A power-supply voltage sensing device is disclosed, which relates to a technology for detecting a level of an external power-supply voltage during a test mode. The power-supply voltage sensing device includes a reference voltage trimming unit configured to trim a reference voltage in response to a code signal, a power-supply voltage detection unit configured to select one of a power-supply voltage and an external power-supply voltage in response to a test signal, compare the external power-supply voltage with the reference voltage, and output a detection signal according to the result of comparison, and a reference voltage control unit configured to output the code signal in response to the detection signal.

A calibration circuit providing a programmable voltage generator that is selectively connectable to a first capacitor plate of a capacitive structure to supply a voltage thereto. A reference voltage generator is coupled to the output of the programmable voltage generator and generates a reference voltage. A comparator receives the reference voltage and a discharging voltage from the capacitive structure during a discharge period and, based on those inputs, generates a signal that is output to a digital controller. A constant current source is selectively connectable to the capacitive structure to generate a constant current. Based on the output of the comparator, the constant current, and a count representing a time during which the discharging voltage decreases, the digital controller measures capacitance to calibrate a movable mirror of the capacitive structure. During calibration, the digital controller controls the programmable voltage generator and a second capacitor plate of the capacitive structure.

A calibration circuit providing a programmable voltage generator that is selectively connectable to a first capacitor plate of a capacitive structure to supply a voltage thereto. A reference voltage generator is coupled to the output of the programmable voltage generator and generates a reference voltage. A comparator receives the reference voltage and a discharging voltage from the capacitive structure during a discharge period and, based on those inputs, generates a signal that is output to a digital controller. A constant current source is selectively connectable to the capacitive structure to generate a constant current. Based on the output of the comparator, the constant current, and a count representing a time during which the discharging voltage decreases, the digital controller measures capacitance to calibrate a movable mirror of the capacitive structure. During calibration, the digital controller controls the programmable voltage generator and a second capacitor plate of the capacitive structure.