Abstract: A system comprises an inverter configured to convert DC power from a battery to AC power to drive a motor, wherein the inverter includes: a galvanic isolator separating a high voltage area from a low voltage area; a low voltage phase controller in the low voltage area, the low voltage phase controller configured to receive a pulse width modulation (PWM) signal from an inverter controller and adjust the received PWM signal based on a feedback signal; and a high voltage phase controller in the high voltage area, the high voltage phase controller configured to receive the adjusted PWM signal from the low voltage phase controller, provide the adjusted PWM signal to a phase switch, and provide the feedback signal based on an on-time measurement of the phase switch.

Abstract: A method for fail-safe resolver excitation includes generating a resolver excitation signal and providing the resolver excitation signal to an input of a first resolver control circuit and to an input of a second resolver control circuit. The method also includes, in response to the first resolver control circuit detecting a fault in the resolver excitation signal provided to the first resolver control circuit: biasing, using the first resolver control circuit, a first resolver amplifier; and communicating, via a communication bus between the first resolver control circuit and the second resolver control circuit, an indication to the second resolver control circuit that the first resolver control circuit detected the fault in the resolver excitation signal provided to the first resolver control circuit.

Abstract: A method for fail-safe resolver excitation includes generating a resolver excitation signal and providing the resolver excitation signal to an input of a first resolver control circuit and to an input of a second resolver control circuit. The method also includes, in response to the first resolver control circuit detecting a fault in the resolver excitation signal provided to the first resolver control circuit: biasing, using the first resolver control circuit, a first resolver amplifier; and communicating, via a communication bus between the first resolver control circuit and the second resolver control circuit, an indication to the second resolver control circuit that the first resolver control circuit detected the fault in the resolver excitation signal provided to the first resolver control circuit.

Abstract: An apparatus includes a first analog-to-digital converter configured to measure a first reference voltage and a third reference voltage. The apparatus also includes a second analog-to-digital converter configured to measure a second reference voltage and a fourth reference voltage. The apparatus also includes a controller configured to calculate a first resistance ratio, and determine a positive high voltage associated with the positive high voltage direct current input signal based, at least in part, on the first resistance ratio. The controller is further configured to calculate a second resistance ratio, and determine a negative high voltage associated with the negative high voltage direct current input signal based, at least in part, on the second resistance ratio.

Abstract: A method for regulating a power conditioner output voltage level includes monitoring a first voltage level of a first supply source and a second voltage level of a second supply source and, while the power conditioner is being supplied by the first supply source, controlling a duty-cycle of an output switch of the power conditioner with feedback-based control signals generated based on errors between a target voltage level and samples of the output voltage level obtained at an output voltage sampling frequency. The method also includes, controlling, for a period corresponding to the output voltage sampling frequency, the duty-cycle of the output switch with an estimated control signal. The method also includes, while the power conditioner is being supplied by the second supply source, controlling the duty-cycle of the output switch using the feedback-based control signals.

Abstract: A battery monitor system for determining a cell voltage between a low side contact and a high side contact of a cell in situ as one of a plurality of cells connected in series to form a battery. The system uses an arrangement of switches and capacitors to shift relatively high absolute voltages of a battery stack to a relative low voltage level so lower voltage electronics can be used to monitor cell voltages. The system may be configured to provide a single ended measurement or a differential measurement indicative of a cell voltage. The differential measurement may be advantageous to correct or offset signal noise caused by electromagnetic interference (EMI).

Abstract: A battery monitor system for determining a cell voltage between a low side contact and a high side contact of a cell in situ as one of a plurality of cells connected in series to form a battery. The system uses an arrangement of switches and capacitors to shift relatively high absolute voltages of a battery stack to a relative low voltage level so lower voltage electronics can be used to monitor cell voltages. The system may be configured to provide a single ended measurement or a differential measurement indicative of a cell voltage. The differential measurement may be advantageous to correct or offset signal noise caused by electromagnetic interference (EMI).

Abstract: A system and method are provided for communicating data synchronously with a plurality of crash sensors onboard a vehicle. The system includes a control unit comprising interface circuitry for communicating with a plurality of crash sensors and providing synchronization signals to the crash sensors. The system also includes a communication bus coupled to the control unit for communicating with the crash sensors. The system further includes a plurality of crash sensors connected to the communication bus for communicating with the control unit. Each of the plurality of crash sensors receives one or more synchronization signals and is capable of transmitting data in response to the synchronous signals. The plurality of crash sensors each comprises logic for comparing a sensed parameter to a threshold and transmitting data when the sensed parameter exceeds the threshold.

Abstract: Analog signal conditioning circuitry is provided for processing an analog signal generated by a sensor to remove DC offset. The signal conditioning circuitry includes an amplifier having the first input receiving an analog input signal and a second input receiving a reference signal. The amplifier includes an output providing an analog output signal defined by an amplified representation of the analog input signal and the reference signal. The circuitry includes a feedback circuit having an input coupled to the amplifier output and an output coupled to the first input of the amplifier for providing an analog feedback signal. The feedback circuit includes an analog-to-digital converter for converting the analog amplifier output to a digital signal, a digital controller for processing the digital signal, and a digital to analog converter for converting the processed digital signal to an analog feedback signal.

Abstract: Analog signal conditioning circuitry is provided for processing an analog signal generated by a sensor to remove DC offset. The signal conditioning circuitry includes an amplifier having the first input receiving an analog input signal and a second input receiving a reference signal. The amplifier includes an output providing an analog output signal defined by an amplified representation of the analog input signal and the reference signal. The circuitry includes a feedback circuit having an input coupled to the amplifier output and an output coupled to the first input of the amplifier for providing an analog feedback signal. The feedback circuit includes an analog-to-digital converter for converting the analog amplifier output to a digital signal, a digital controller for processing the digital signal, and a digital to analog converter for converting the processed digital signal to an analog feedback signal.

Abstract: In accordance with the teachings of the present invention, a fault detection circuit is provided which detects short circuits on differential leads associated with a magnetic sensor and modifies said differential voltage to avoid possible errors associated with a short circuit. The circuit includes a first and second input coupled to first and second signal lines for receiving a differential voltage. A first voltage comparator compares voltage potentials at the first and second signal lines so as to detect equal voltage crossings and provide an output in response thereto. A rectifier is coupled to the first and second signal lines in the output of the first comparator and has first and second outputs for producing positive half-wave voltage cycles with a voltage potential at each of the first and second lead lines. A second comparator is provided for comparing the half-wave voltage cycles with a first threshold voltage that represents a short circuit power source.

Abstract: In accordance with the teachings of the present invention, an adaptive threshold circuit is provided which develops a series of square-wave voltage pulses from an alternating differential voltage that is produced in response to the rotation of a wheel. The adaptive threshold circuit includes an input circuit for providing an input voltage in response to the alternating differential voltage. A first voltage comparator compares the input voltage with an adaptive analog threshold voltage and produces an output in response thereto which causes a rising edge of the square-wave voltage pulse. A second voltage comparator compares a selected portion of the input voltage with the adaptive analog threshold voltage and produces an output in response thereto. The adaptive threshold circuit further includes a binary counter having a reset input for receiving the first voltage comparator output and an enable input for receiving the second voltage comparator output and provides a plurality of binary outputs.

Abstract: An adaptive loading circuit is provided for adaptively attenuating an alternating differential voltage that is produced by a magnetic sensor in response to the rotation of a wheel while maintaining noise immunity. The circuit includes an input for receiving an input differential voltage from the magnetic sensor via first and second input lines. A resistive divider network is included which has a resistive load serially connected to each of the first and second input lines and a plurality of adaptively selectable parallel resistive loads connected between the first and second input lines. Combinations of the parallel resistive loads are adaptively selected when the input differential voltage exceeds predetermined voltage thresholds so as to divide the input differential voltage into a selected portion thereof as an output differential voltage. In addition, the parallel resistive loads may be selectively switched out when the input differential voltage drops below a low voltage threshold.