Abstract: Systems and methods for cell anomaly detection are provided. The disclosed systems and methods of cell anomaly detection may use a single circuit to detect both cell-open and imbalance conditions. Disclosed embodiments may incorporate a continuous or a sampled time system (i.e. cell anomaly detection is performed when an enable signal is active). An example embodiment includes receiving voltages of a plurality of cells of a battery pack; converting the received voltages to currents; determining a maximum current of the currents; determining whether at least one of the currents is anomalous; and reporting the at least one anomalous current as indicative of a bad cell.

Abstract: One embodiment includes a power system. The system includes a power switch device that is activated to provide an output voltage to a load in response to an input voltage. The power switch device includes a control terminal and a bulk connection. The system also includes a reverse voltage control circuit configured to passively couple the input voltage to one of the control terminal and the bulk connection in response to a reverse voltage condition in which an amplitude of the input voltage becomes negative. The system further includes an output shutoff circuit configured to passively couple the output voltage to a neutral-voltage rail during the reverse voltage condition.

Abstract: One embodiment includes a power system. The system includes a power switch device that is activated to provide an output voltage to a load in response to an input voltage. The power switch device includes a control terminal and a bulk connection. The system also includes a reverse voltage control circuit configured to passively couple the input voltage to one of the control terminal and the bulk connection in response to a reverse voltage condition in which an amplitude of the input voltage becomes negative. The system further includes an output shutoff circuit configured to passively couple the output voltage to a neutral-voltage rail during the reverse voltage condition.

Abstract: Systems and methods are provided for monitoring a voltage. A level shifter is configured to generate a current proportional to the voltage of the battery cell. A delta-sigma modulator is configured to convert the current into a first density modulated bitstream representing the voltage of the battery cell. A first reference source is configured to provide a second density modulated bitstream representing a first threshold voltage. A first comparator is configured to compare the first density modulated bitstream and the second density modulated bitstream.

Abstract: Systems and methods for analog to digital conversion charge storage device measurement are presented. In multi-cell charge storage device monitoring systems, accurate measurement of cell voltages is used for protection of the multi-cell device. The disclosed cell referenced solution converts the cell voltage to a digital representation referenced at the cell voltage. The digital representation referenced to the cell voltage is then level shifted to a ground referenced signal suitable for digital post processing. This processing may be used for fault detection of over-voltage, under-voltage, open cell, and similar fault conditions and cell capacity measurements. An example embodiment implements a sigma delta modulator to perform the signal transformation from analog to digital. The disclosed systems and methods may be differential and stackable for multiple cells.

Abstract: Various apparatuses and methods for detecting cell connection status of a multi-cell battery are disclosed herein. For example, some embodiments provide an apparatus for detecting cell connection status of a multi-cell battery. The apparatus includes a battery cell input for each cell, a cell connection status detector for each cell, and at least one comparator. Each of the cell connection status detectors is connected to a battery cell input and has a current-based status indicator output. The at least one comparator is connected to the current-based status indicator outputs. Each of the plurality of cell connection status detectors floats in a different supply voltage range. The at least one comparator is referenced to a lower voltage potential than at least one of the plurality of cell connection status detectors.

Abstract: Systems and methods for analog to digital conversion charge storage device measurement are presented. In multi-cell charge storage device monitoring systems, accurate measurement of cell voltages is used for protection of the multi-cell device. The disclosed cell referenced solution converts the cell voltage to a digital representation referenced at the cell voltage. The digital representation referenced to the cell voltage is then level shifted to a ground referenced signal suitable for digital post processing. This processing may be used for fault detection of over-voltage, under-voltage, open cell, and similar fault conditions and cell capacity measurements. An example embodiment implements a sigma delta modulator to perform the signal transformation from analog to digital. The disclosed systems and methods may be differential and stackable for multiple cells.

Abstract: A system is provided for generating a plurality of different voltage level clock signals. The system comprises an electrical energy storage pack having a plurality of series coupled electrical energy storage cells that provide a plurality of different output voltage level, a reference oscillator that provides a reference clock signal and a plurality of voltage clamps that receive the plurality of different output voltage levels and output the plurality of different voltage level clock signals at respective output nodes. The plurality of voltage clamps are configured to clamp each of a given output node to a respective high-side voltage level in response to pulling up of the given output node toward a respective high output voltage level and to clamp each of the given output node to a respective low-side voltage level in response to pulling down of the output node toward a low output voltage level.

Abstract: Systems and methods are provided for monitoring a voltage. A level shifter is configured to generate a current proportional to the voltage of the battery cell. A delta-sigma modulator is configured to convert the current into a first density modulated bitstream representing the voltage of the battery cell. A first reference source is configured to provide a second density modulated bitstream representing a first threshold voltage. A first comparator is configured to compare the first density modulated bitstream and the second density modulated bitstream.

Abstract: A system is provided for generating a plurality of different voltage level clock signals. The system comprises an electrical energy storage pack having a plurality of series coupled electrical energy storage cells that provide a plurality of different output voltage level, a reference oscillator that provides a reference clock signal and a plurality of voltage clamps that receive the plurality of different output voltage levels and output the plurality of different voltage level clock signals at respective output nodes. The plurality of voltage clamps are configured to clamp each of a given output node to a respective high-side voltage level in response to pulling up of the given output node toward a respective high output voltage level and to clamp each of the given output node to a respective low-side voltage level in response to pulling down of the output node toward a low output voltage level.

Abstract: Systems and methods for overvoltage and undervoltage detection may be implemented with a fully differential circuit that includes a coarse comparator and a band gap based fine comparator. The coarse comparator may determine if the battery is closer to an OV condition or an UV condition. Based on the output of the coarse comparator, the trip point of the fine comparator is adjusted. The outputs of both comparators are pull-up circuits whose output is decoded to determine if an OV or a UV condition has occurred. The systems and methods accomplish valid circuit outputs even when the voltage across the battery reduces to zero volts. This may be achieved by using an active low signal for the UV condition and an active high signal for the OV condition. Thus, when the battery voltage goes to zero, the circuit evaluates to the correct output.

Abstract: Various apparatuses and methods for detecting cell connection status of a multi-cell battery are disclosed herein. For example, some embodiments provide an apparatus for detecting cell connection status of a multi-cell battery. The apparatus includes a battery cell input for each cell, a cell connection status detector for each cell, and at least one comparator. Each of the cell connection status detectors is connected to a battery cell input and has a current-based status indicator output. The at least one comparator is connected to the current-based status indicator outputs. Each of the plurality of cell connection status detectors floats in a different supply voltage range. The at least one comparator is referenced to a lower voltage potential than at least one of the plurality of cell connection status detectors.

Abstract: Systems and methods for overvoltage and undervoltage detection are provided. The disclosed systems and methods of overvoltage and undervoltage detection may be implemented with a fully differential circuit that includes a coarse comparator and a band gap based fine comparator. The coarse comparator may determine if the battery is closer to an OV condition or an UV condition. Based on the output of the coarse comparator, the trip point of the fine comparator is adjusted. The outputs of both comparators are pull-up circuits whose output is decoded to determine if an OV or a UV condition has occurred. The disclosed systems and methods of overvoltage and undervoltage detection accomplish valid circuit outputs even when the voltage across the battery reduces to zero volts. This may be achieved by using an active low signal for the UV condition and an active high signal for the OV condition. Thus, when the battery voltage goes to zero, the circuit evaluates to the correct output.

Abstract: Systems and methods for cell anomaly detection are provided. The disclosed systems and methods of cell anomaly detection may use a single circuit to detect both cell-open and imbalance conditions. Disclosed embodiments may incorporate a continuous or a sampled time system (i.e. cell anomaly detection is performed when an enable signal is active). An example embodiment includes receiving voltages of a plurality of cells of a battery pack; converting the received voltages to currents; determining a maximum current of the currents; determining whether at least one of the currents is anomalous; and reporting the at least one anomalous current as indicative of a bad cell.